General Tuning Guide (Updated 1.09)

[Stotty]

Wow sorry guys, I didn't get any notifications for any of this so apologies for the delay.

No worries 👍

Camber- There are a few tricks that need to be applied to make camber work correctly and it is not a fix all solution by any means. When setting camber you need to adjust your Toe settings as the two are very much linked, I'm working on a guide to relative adjustments but it will take a while to collect the data. Camber can be very beneficial on some tracks and a hindrance on others, the same goes for the car you are using and how you are using it. I would never say that you must use camber to make your car fast, it just doesn't work like that.

I'd be interested in seeing some examples of camber interacting with toe and how they can be jointly tuned to improve performance vs camber at 0 0. My experience is camber reduce grip, so if there's a way to improve its effect, I'd love to see it 👍

LSD Initial - Lower settings are definitely "open", A fully locked diff would be 60/60/60. The thing you are experiencing is not the effect of a locked diff but more the effect of a load spike when going from throttle to lifting. At extremes (ie. 5/60/5 60/60/60) the effect feels very similar but it is a different cause entirely.
If you try both of them you will notice that the 5/60/5 rotates very suddenly when the throttle is lifted, this is because its gone from locked (wheels spinning at the same speed) to open (wheels can spin at vastly different speeds allowing faster rotation). The one set at 60/60/60 will have no sudden snap round because there is no change in differential wheel speed during different phases.
The diff engages softer at higher numbers because the change in wheel speed between various phases is lessened and therefore less violent. The Initial is just pre-load, it sets the baseline amount of differential speed between the two wheels, the lower the setting, the higher the speed differential can be, any setting set lower than the Initial won't work properly.

Hmmmm... I'm not disagreeing with the real life theory, but that's not my experience of how the diff affects cars in GT6 (or in GT5).

The higher I set the initial, the higher I need to set the accel to get the same drive out of corners... and the better the driver, the higher the accel they can manage.

I always understood initial to be the amount of wheel speed differential required to get the diff to engage... the speed at which the diff reacts to changes in wheel speed. So a low number means the diff needs less wheel speed differential to bring the accel in to play (and vice versa).

Typically, I would almost always use 5 for initial, then I'd adjust the accel from a starting point of 20. If the car is too tail happy on exits, I would decrease the accel, if the car is fine on exits I would increase the accel until I got too much oversteer.

For decel, I always use 5 unless the car is VERY unstable under trail braking and I can't manage that properly with rear toe and brake balance (some MR & RR cars). This gives the maximum entry rotation, which is fastest if you can manage it.

So a typical diff setting for me would be 5 20 5. For drifting, I use 5 60 5.

I've never really felt initial has any effect on decel - but I haven't tested it!!

Power/Torque - Never dismiss the importance of torque and the original question referred to limited to bhp levels. At the very top end of performance cars BHP is generally the deciding factor because it allows you to gain a lot of speed when you are not moving a lot of weight. In less specialised road vehicles torque can be way more important for dragging your heavy ass out of a slow corner so you can utilise the BHP more. Less torque does not mean more power, torque and BHP are the same thing described in different ways after all.

Again, not my experience from running numerous TT's across many different cars and tyre compounds, some powerful, some not.

Might be true when you're limiting for a specific BHP level (as in your analysis above), but when do you typically tune for a BHP limit? Power Points are the typical limiting factor. And when you use the power limiter to get down to a PPT limit, maximising BHP over torque has always proven to produce the fastest lap times.

 

[DolHaus]

No worries 👍

I'd be interested in seeing some examples of camber interacting with toe and how they can be jointly tuned to improve performance vs camber at 0 0. My experience is camber reduce grip, so if there's a way to improve its effect, I'd love to see it 👍

At this point he closest I can give to an answer is that the more camber you run, the more Toe Out you need to run to correct the cars alignment. Adding camber is having a similar effect to Toe In, you get more mid corner grip but your initial turn in is less sharp. To combat this we use toe out to regain the initial turn in and sharpness. We can basically have the best of both worlds rather that being the best compromise.

1.0 Front camber = -0.18 Front toe
2.0 Front camber = -0.40 Front toe

No worries 👍

Hmmmm... I'm not disagreeing with the real life theory, but that's not my experience of how the diff affects cars in GT6 (or in GT5).

The higher I set the initial, the higher I need to set the accel to get the same drive out of corners... and the better the driver, the higher the accel they can manage.

I always understood initial to be the amount of wheel speed differential required to get the diff to engage... the speed at which the diff reacts to changes in wheel speed. So a low number means the diff needs less wheel speed differential to bring the accel in to play (and vice versa).

Typically, I would almost always use 5 for initial, then I'd adjust the accel from a starting point of 20. If the car is too tail happy on exits, I would decrease the accel, if the car is fine on exits I would increase the accel until I got too much oversteer.

For decel, I always use 5 unless the car is VERY unstable under trail braking and I can't manage that properly with rear toe and brake balance (some MR & RR cars). This gives the maximum entry rotation, which is fastest if you can manage it.

So a typical diff setting for me would be 5 20 5. For drifting, I use 5 60 5.

I've never really felt initial has any effect on decel - but I haven't tested it!!

None of that is real life theory, its all in game stuff.

Initial is the baseline setting and what is acting upon the the drive wheels while rolling without brake or throttle applied.

Accel/Decel are separate settings from the Initial, when you are on the gas you are in the Accel phase, when you are on the brakes you are in the Decel phase.

All the numbers represent is how much speed differential there can potentially be between the drive wheels.
A lower number means there can be a greater speed differential and therefore axis rotation is more easy (the outside wheel travels further round a corner than the inside and therefore needs to rotate faster).
A higher number means that the wheels travel at a more similar speed which makes them resist axis rotation and even cause outside wheel slip in extreme cases.

Here is a simple test for any LSD setting:-

First we will test Initial on a RWD car

Pick a corner
Set your Initial to 5
Drive into that corner and lift off the throttle
Turn into the corner while still off the throttle and note how responsive and easy to turn in the car was
Set your Initial to 30
Drive into that corner and lift off the throttle
Turn into the corner while still off the throttle and note how responsive and easy to turn in the car was

You will find that the car understeers a lot more and feels like the rear is way more reluctant to rotate. This is because the diff is preventing the outside wheel from turning at the higher speed it require to make the turn without slipping.


Next we will test Accel on a RWD car

Pick a corner
Set your Accel to 10
Turn into the corner and line up your exit, nail the throttle and note how much rotation is possible on exit
Set your Accel to 30
Turn into the corner and line up your exit, nail the throttle and note how much rotation is possible on exit

You will find that the car pushes wider and wider as you increase the accel value for the same reason as above.


I'm sure you can figure out how to do decel on your own.


The relationship between Initial and Accel/Decel is very important because of the way it can affect the car during various phases.

Lets imagine that you have your 5/20/5 settings and you are going round a long sweeping bend at 100mph. I will use some percentages to illustrate the point but these should not be taken as fact.

Lets say that when set to 5 the outside wheel can spin 100% faster than the inside
When set to 20 the outside wheel can spin 50% faster than the inside.

You are going round the corner at full throttle and the Diff is in the Accel phase. Your inside wheel is spinning at 100mph and your outside wheel is spinning at 150mph.
You notice the car is starting to drift wide so you decide to lift off the throttle in order to get the nose pointed back in. When you lift off the throttle and the Diff enters the Initial phase, this means that the inside wheel is still spinning at 100mph but your outside wheel can now spin at up to 200mph.
This sudden change in speed unbalances the car and allows the car to over-rotate leading to instability and probably a spin.

The larger the gap between Accel/Decel and Initial, the more pronounced the effect will be when switching between phases. If it is too high then the transition will cause a load spike and overcome the tyres leading to a complete loss of grip.

You can get reasonable results by using 'base' settings but you will get way better results if you actually spend time working out how the diff is affecting the drive wheels and how it could be improved. If you want to be fast then you've got to understand how your power is getting from the engine to the wheels, its one of the most dominant and key features on any car and should be treated as a high priority component.

 

[Stotty]

Thanks for the very comprehensive reply 👍

At this point he closest I can give to an answer is that the more camber you run, the more Toe Out you need to run to correct the cars alignment. Adding camber is having a similar effect to Toe In, you get more mid corner grip but your initial turn in is less sharp. To combat this we use toe out to regain the initial turn in and sharpness. We can basically have the best of both worlds rather that being the best compromise.

1.0 Front camber = -0.18 Front toe
2.0 Front camber = -0.40 Front toe

If what you’re saying is true, GT6 suspension geometry is even more screwed up than I thought it already was I’ve never heard of having to add toe as you add negative camber. When I had some extra camber on the front of my car the alignment guy didn’t need to adjust the toe!

Also... are you saying 1.0/-0.18 actually gives more grip than 0/0?

-0.40 is a huge amount of front toe... rare I’d need to use any more than -0.10 in GT6!!

None of that is real life theory, its all in game stuff.

Initial is the baseline setting and what is acting upon the drive wheels while rolling without brake or throttle applied.

Accel/Decel are separate settings from the Initial, when you are on the gas you are in the Accel phase, when you are on the brakes you are in the Decel phase.

I understand how a diff works, and we are in agreement over accel and decel 👍

The question is how Initial affects accel/decel.

I’ve pulled out the section above as the diff doesn’t know if you’re braking or not, only if the car is slowing – ie; could be you’ve braked or could be you’ve just lifted off and the car is slowing under ‘engine braking’.

There’s no direct link between the brakes and the diff.

First we will test Initial on a RWD car

Pick a corner

Set your Initial to 5
Drive into that corner and lift off the throttle
Turn into the corner while still off the throttle and note how responsive and easy to turn in the car was

Set your Initial to 30
Drive into that corner and lift off the throttle
Turn into the corner while still off the throttle and note how responsive and easy to turn in the car was

Will test when I can get on my PS3 👍

You can get reasonable results by using 'base' settings but you will get way better results if you actually spend time working out how the diff is affecting the drive wheels and how it could be improved. If you want to be fast then you've got to understand how your power is getting from the engine to the wheels, its one of the most dominant and key features on any car and should be treated as a high priority component.

Yes, I know that. The Diff, alongside rear toe and ride height has the most pronounced affect on a cars handling/balance in GT (excluding ballast).

And I without wanting to sound rude or arrogant, I am already reasonably quick... but we can all get quicker

 

[DolHaus]

If what you’re saying is true, GT6 suspension geometry is even more screwed up than I thought it already was I’ve never heard of having to add toe as you add negative camber. When I had some extra camber on the front of my car the alignment guy didn’t need to adjust the toe!

Also... are you saying 1.0/-0.18 actually gives more grip than 0/0?

-0.40 is a huge amount of front toe... rare I’d need to use any more than -0.10 in GT6!!

Its to do with the way camber thrust works and how that alters the direction each wheel wants to travel. Its kind of complicated in terms of physics but the basic principal is simple enough to visualise.
If we think about how a motorbike turns a corner we notice that to go left they lean on the left side of the tyre and the bike travels in an arc. This is camber thrust in action, the tyre is pushing back in response to the effect of leaning and pushing the bike in which ever direction.

(car set at 0.00 toe)
When we add camber we are leaning the tyre inwards and as a result the direction of travel would look similar to the effects of Toe In. The lines of travel from each cambered wheel will be pointing in towards the centre rather than the 0.00 Toe that is listed suggests. The more camber you add, the more Toe-In-like effect is.

We basically use an amount of Toe Out to correct the Toe-In-like effect of the camber leaning the wheels and return the characteristics back to a familiar point. The settings I have listed are for reference when trying to find the point that would be most similar in terms of feel to 0.00. When setting toe I would generally start at 0.00 and then adjust to suit my needs, when testing camber the reference numbers help me to retain that reference point for testing purposes.

I am by no means saying that a car will be unconditionally quicker with camber, I am simply saying that it has the potential to be given the right circumstances. Its a tricky beast, you only have to watch a few motor races at various circuits to realise how much it can change from car to car and track to track depending on a whole host of things. For that reason it can't be dismissed completely, given the right car on the right track and running the right setup, camber could be unbeatable. Having the reference numbers means I can experiment with the camber settings and make changes fairly quickly during testing rather than putting some camber on and spending and age trying to work out why my car suddenly feels like crap.

If I'm at the end of a build and at the stage of setting toe/camber and my car is currently running 0.00/0.0 on the front I know that if I want to throw on some camber for testing I will have to adjust the toe in a certain way in order to best maintain the 0.00 Toe feel. I can say with some degree of accuracy that if I want to stick 1.5 Camber on the front then I should be looking to set the Toe within a few clicks of -0.30.

I've never been a massive fan of heavy Toe settings either, I rarely used double figures in either direction, but in this case it doesn't have the effect you'd expect.

The question is how Initial affects accel/decel.

I’ve pulled out the section above as the diff doesn’t know if you’re braking or not, only if the car is slowing – ie; could be you’ve braked or could be you’ve just lifted off and the car is slowing under ‘engine braking’.

There’s no direct link between the brakes and the diff.

The Initial has no direct effect on either but instead heavily influences the transition between Initial/Accel and Initial/Decel phases.

In real life an LSD would rely on the amount of torque coming from the input shaft and the resistive force from the wheel to adjust the gearing ratio via spring loaded conical gears, it uses the torque forces to compress the springs and alter the differential speeds.

In game its way simpler to simulate because you have 3 basic inputs to designate which phase you are in, accelerator, brakes and neutral (no input).
When you are on the gas you are in the Accel phase
When you are on the brakes you are in the Decel phase
When you are not making any inputs you are in the Initial phase

There is a transition period between each setting that is based on the amount of input you are making, the % difference between wheel speeds increase/decrease depending on the value of each setting. The larger the numerical gap, the faster and more violent the % transition will be.
I have noticed that instead of being a linear progression from 5-60 the lower (open) settings appear to have a much more dramatic % difference between settings than the higher (locked) settings.
To illustrate this idea a bit better we will say that when set at 5 the difference is 100%, when set at 60 it is 0%.
5 - 15 = 100% - 50%
15 - 40 = 50% - 15%
40 - 60 = 15% - 0%

As we can see the % change per unit in the lower figures is much more dramatic than when dealing with higher numbers. This means that when we adjust our low Initial it has a dramatic effect on the scale of the transition, if we were raising the value we would feel a much smoother transition between neutral and accelerator phases which could easily be mistaken for a direct effect on the Accel values. The values are still separate and not affecting each other in any way, only the transition has been altered.

 

[Stotty]

Its to do with the way camber thrust

When we add camber we are leaning the tyre inwards and as a result the direction of travel would look similar to the effects of Toe In. The lines of travel from each cambered wheel will be pointing in towards the centre rather than the 0.00 Toe that is listed suggests. The more camber you add, the more Toe-In-like effect is.

Yes, I understand camber thrust, but last time I looked at the alignment sheet for my own car, this was a tiny measurement, and there was no need to add loads of toe to the car. When I changed from stock 0 to 1.5* some years ago, there was no alterations needed to toe to compensate.

Its a tricky beast, you only have to watch a few motor races at various circuits to realise how much it can change from car to car and track to track depending on a whole host of things. For that reason it can't be dismissed completely, given the right car on the right track and running the right setup, camber could be unbeatable. Having the reference numbers means I can experiment with the camber settings and make changes fairly quickly during testing rather than putting some camber on and spending and age trying to work out why my car suddenly feels like crap.

I don’t take much notice of real life when considering GT settings... far too many black holes in the physics engine for RL to e relevant

The Initial has no direct effect on either but instead heavily influences the transition between Initial/Accel and Initial/Decel phases.

In game its way simpler to simulate because you have 3 basic inputs to designate which phase you are in, accelerator, brakes and neutral (no input).
When you are on the gas you are in the Accel phase
When you are on the brakes you are in the Decel phase
When you are not making any inputs you are in the Initial phase

I’m assuming you’ve done a heap of testing running no ABS?

If you’ve run with ABS your conclusions are masked by the stability assist ABS gives in GT6 – in so far as braking is completely unrealistic... brake release oversteer for example.

This means that when we adjust our low Initial it has a dramatic effect on the scale of the transition, if we were raising the value we would feel a much smoother transition between neutral and accelerator phases which could easily be mistaken for a direct effect on the Accel values. The values are still separate and not affecting each other in any way, only the transition has been altered.

I think we agree...

A low initial allows a fast transition from open to locked... so a lower value (5 for example) allows the diff to move from locked accel to locked decl very quickly – potentially making the car unstable.

Therefore a car with 5 60 5, will lock quickly when you hit the gas, and open quickly (and stay open) when you release the gas or brake.

A car with 60 60 60 will be very stable in transition.

I admit 5 60 60 isn’t a locked diff in real life, but the nature of how initial works in GT6 means it’s how you would replicate it in the game. 5 best replicates the instant transition you get with a proper locked dif.

5 60 5 would be the most potentially unstable setting, but would also offer the best combination of entry rotation. and exit speed.

This is why, when you look at the tunes of the very fastest drivers in the Seasonal TT's, you generally see 5 (a relatively high number) 5, the accel being the limiting factor. They have the braking/steering skills to manage a very unstable car on entry, and have the throttle control to manage traction on the way out... the fastest way round a track

 

[DolHaus]

Yes, I understand camber thrust, but last time I looked at the alignment sheet for my own car, this was a tiny measurement, and there was no need to add loads of toe to the car. When I changed from stock 0 to 1.5* some years ago, there was no alterations needed to toe to compensate.

I don’t take much notice of real life when considering GT settings... far too many black holes in the physics engine for RL to e relevant

A bit of a mixed message there
Just trust me on the numbers, they might not be true to life but they do work.

I’m assuming you’ve done a heap of testing running no ABS?

If you’ve run with ABS your conclusions are masked by the stability assist ABS gives in GT6 – in so far as braking is completely unrealistic... brake release oversteer for example.

Don't start the ABS 0 debate and please come down off your high horse, I won't be spoken down to like that in my own thread when I am trying my best to answer your questions. I've both tuned and driven ABS 0 and it has very little effect on the overall function of the LSD, I might adjust the initial/decel by a tick but nothing dramatic.

There is definitely a connection between decel and braking, why wouldn't there be? Try raising your Decel settings to 30 and tell me it doesn't have a profound effect on how easy the car is to rotate during hard braking.

Brake release oversteer can be caused by many things, I don't see what point you are trying to make there?

I think we agree...

A low initial allows a fast transition from open to locked... so a lower value (5 for example) allows the diff to move from locked accel to locked decl very quickly – potentially making the car unstable.

Therefore a car with 5 60 5, will lock quickly when you hit the gas, and open quickly (and stay open) when you release the gas or brake.

A car with 60 60 60 will be very stable in transition.

I admit 5 60 60 isn’t a locked diff in real life, but the nature of how initial works in GT6 means it’s how you would replicate it in the game. 5 best replicates the instant transition you get with a proper locked dif.

5 60 5 would be the most potentially unstable setting, but would also offer the best combination of entry rotation. and exit speed.

This is why, when you look at the tunes of the very fastest drivers in the Seasonal TT's, you generally see 5 (a relatively high number) 5, the accel being the limiting factor. They have the braking/steering skills to manage a very unstable car on entry, and have the throttle control to manage traction on the way out... the fastest way round a track

You are making broad sweeping statements that are simply not true.

A low Initial does not allow a fast transition, the numerical distance between Initial/Accel or Initial/Decel dictates the speed of the change.

If you set a low Initial and a low Accel then the transition will be smooth
If you set a low Initial and a high Accel the transition will be violent
If you set a mid Initial and a high Accel the transition will be less dramatic but still noticeable
If you set a high Initial and a high Accel the transition will be smooth

The number dictates how effectively the car can rotate during each phase
The numerical distance between each setting dictates how the transition will feel

The 60/60/60 diff is constant, the outside and inside wheel are always spinning at the same speed regardless of input type. This represents a true locked differential, the rear axle might as well be a solid beam connecting the two wheels.

The 5/60/5 is only locked during acceleration, as soon as you lift or apply the brakes the differential becomes completely open and the drive wheels are free to do what ever the hell the want. This allows for sudden direction change when lifting.

 

[Aussie_HSV]

Hi DolHaus,
As usual I'm keeping a close eye on all things said here. 👍
Appreciate the rough guide you've given regarding camber and toe.
I also notice you've added a bit to the camber and toe section to your guide since end of June which I've been trying to digest, so that's been excellent.
TBH, I'm struggling to find any benefit from camber since 1.09 but that's just me fumbling around with it like a fool.
I'm sure I'll crack the code at some stage.

Anyway, without wishing to question either yourself of Hami, I've found an inconsistency between your descriptions.
It's regarding front toe.

Your guide states:
Front toe in (+ Slider to the right)
Pros: Improved straight line stability. Increased mid corner grip
Cons: Reduced grip on turn in

Front toe out (- Slider to the left)
Pros: Increased grip on turn in
Cons: Less stable at speed. Reduced mid corner grip.

And Hami's guide states:
Toe Angle
- Front toe-in will increase entry turn in, but also reduces mid-corner to exit grip
- Front toe-out will increase mid-corner to exit grip, but also reduces entry turn in



I'm chasing mid corner grip in an attempt to help reduce tyre wear on a 'very fast' degradation event.
So I came looking through the bibles.

Is it just my way of reading those descriptions, or are the two of you at odds regarding front toe in and toe out?
I thought I had it under control after reading your new camber description but now I'm left second guessing.

Cheers.

 

[GTP_CargoRatt]

@DolHaus

I applaud you on everything you have stated in your last few posts here. Everything you have stated here has been exactly as I have found it to be through my own testing. You are spot on as far as how the camber and toe settings work, exactly how I have also found them to be. I have done hours upon hours of testing and have come up with the same conclusions as you have as far as how camber now works. Its ironic, in a good way, that two people who have never collaborated together before as far as tuning theories go, come up with the exact same conclusions. In my opinion, that pretty much cements things for me as far as camber is concerned. As far as the LSD, I have always understood it to also work the way you have explained so that is really nothing new to me, but great job explaining it for those who do not know how it works. 👍 Great job you are doing here with this thread, you are truly an asset to the community. Keep up the great work my friend.

 

[Thorin Cain]

Hi DolHaus,
As usual I'm keeping a close eye on all things said here. 👍
Appreciate the rough guide you've given regarding camber and toe.
I also notice you've added a bit to the camber and toe section to your guide since end of June which I've been trying to digest, so that's been excellent.
TBH, I'm struggling to find any benefit from camber since 1.09 but that's just me fumbling around with it like a fool.
I'm sure I'll crack the code at some stage.

Anyway, without wishing to question either yourself of Hami, I've found an inconsistency between your descriptions.
It's regarding front toe.

Your guide states:
Front toe in (+ Slider to the right)
Pros: Improved straight line stability. Increased mid corner grip
Cons: Reduced grip on turn in

Front toe out (- Slider to the left)
Pros: Increased grip on turn in
Cons: Less stable at speed. Reduced mid corner grip.

And Hami's guide states:
Toe Angle
- Front toe-in will increase entry turn in, but also reduces mid-corner to exit grip
- Front toe-out will increase mid-corner to exit grip, but also reduces entry turn in



I'm chasing mid corner grip in an attempt to help reduce tyre wear on a 'very fast' degradation event.
So I came looking through the bibles.

Is it just my way of reading those descriptions, or are the two of you at odds regarding front toe in and toe out?
I thought I had it under control after reading your new camber description but now I'm left second guessing.

Cheers.

Hi there Aussie_HSV, I just had a look and you're right. The descriptions are contradictory.

@DolHaus has it spot on, at least that's how it works for me.

@DolHaus

I applaud you on everything you have stated in your last few posts here. Everything you have stated here has been exactly as I have found it to be through my own testing. You are spot on as far as how the camber and toe settings work, exactly how I have also found them to be. I have done hours upon hours of testing and have come up with the same conclusions as you have as far as how camber now works. Its ironic, in a good way, that two people who have never collaborated together before as far as tuning theories go, come up with the exact same conclusions. In my opinion, that pretty much cements things for me as far as camber is concerned. As far as the LSD, I have always understood it to also work the way you have explained so that is really nothing new to me, but great job explaining it for those who do not know how it works. 👍 Great job you are doing here with this thread, you are truly an asset to the community. Keep up the great work my friend.

Could not agree more:tup: Very well said

 

[Stotty]

Just trust me on the numbers, they might not be true to life but they do work.

I'm not much for trusting... I will test myself when I get time, but I was rather hoping you were going to post some of the set ups/examples you have used to come to your conclusions.

Don't start the ABS 0 debate and please come down off your high horse, I won't be spoken down to like that in my own thread when I am trying my best to answer your questions. I've both tuned and driven ABS 0 and it has very little effect on the overall function of the LSD, I might adjust the initial/decel by a tick but nothing dramatic.

There is definitely a connection between decel and braking, why wouldn't there be? Try raising your Decel settings to 30 and tell me it doesn't have a profound effect on how easy the car is to rotate during hard braking.

Sorry if I offended... not my intention 👍

Yes, of course decel effects rotation under braking... but the important (pronounced) effect is when you begin to release the brake pressure whilst trail braking... with ABS 1, the less brake pressure, the more decel affects the car, the more brake pressure, the less decel affects the car.

You are making broad sweeping statements that are simply not true.

A low Initial does not allow a fast transition, the numerical distance between Initial/Accel or Initial/Decel dictates the speed of the change.

If you set a low Initial and a low Accel then the transition will be smooth
If you set a low Initial and a high Accel the transition will be violent
If you set a mid Initial and a high Accel the transition will be less dramatic but still noticeable
If you set a high Initial and a high Accel the transition will be smooth

I’m not making sweeping statements... I’m simply saying when you set the diff up as per my previous post, that’s how the car behaves when you drive it.

And I agree with the way you describe the settings affecting the car as written above.

I’m just confused by your interpretation of Initial...

If you set a low Initial and a high Accel the transition will be violent
If you set a high Initial and a high Accel the transition will be smooth

Then surely Initial affects the rate at which the diff takes up the input load?

It’s the only variable affecting the outcome!

Edit:

In relation to this point...

WThe Initial is just pre-load, it sets the baseline amount of differential speed between the two wheels, the lower the setting, the higher the speed differential can be, any setting set lower than the Initial won't work properly.

I was doing a bit more searching, and I noticed @Motor City Hami has a number of tunes in his garage running higher initial that accel.

MCH is one of the most respected and trusted tuners on the forum and a very decent driver, so you may want to check your assumptions?

 

[Aussie_HSV]

Hi Thorin, cheers mate. 👍
To say I was 'second guessing' was a bad choice of words.
Everything Dolhaus described was very logical and made sense to me.
But me being the information hog that I am, I ventured into Hami's thread as well for some more tid-bits and came across the discrepancy.

I've no doubt Hami would also agree and it's just a simple typo or an accidental flipping of his descriptions.

I appreciate the confirmation in your reply .

 

[Thorin Cain]

Hi Thorin, cheers mate. 👍
To say I was 'second guessing' was a bad choice of words.
Everything Dolhaus described was very logical and made sense to me.
But me being the information hog that I am, I ventured into Hami's thread as well for some more tid-bits and came across the discrepancy.

I've no doubt Hami would also agree and it's just a simple typo or an accidental flipping of his descriptions.

I appreciate the confirmation in your reply .

No problem mate, I get where you're coming from. I actually used Hami's guide first and found a couple of typos like that too. The theory is sound in most of his write up but for some reason, some of the bullet points do seem a little confusing.

 

[DolHaus]

Hi DolHaus,
As usual I'm keeping a close eye on all things said here. 👍
Appreciate the rough guide you've given regarding camber and toe.
I also notice you've added a bit to the camber and toe section to your guide since end of June which I've been trying to digest, so that's been excellent.
TBH, I'm struggling to find any benefit from camber since 1.09 but that's just me fumbling around with it like a fool.
I'm sure I'll crack the code at some stage.

Anyway, without wishing to question either yourself of Hami, I've found an inconsistency between your descriptions.
It's regarding front toe.

Your guide states:
Front toe in (+ Slider to the right)
Pros: Improved straight line stability. Increased mid corner grip
Cons: Reduced grip on turn in

Front toe out (- Slider to the left)
Pros: Increased grip on turn in
Cons: Less stable at speed. Reduced mid corner grip.

And Hami's guide states:
Toe Angle
- Front toe-in will increase entry turn in, but also reduces mid-corner to exit grip
- Front toe-out will increase mid-corner to exit grip, but also reduces entry turn in



I'm chasing mid corner grip in an attempt to help reduce tyre wear on a 'very fast' degradation event.
So I came looking through the bibles.

Is it just my way of reading those descriptions, or are the two of you at odds regarding front toe in and toe out?
I thought I had it under control after reading your new camber description but now I'm left second guessing.

Cheers.

I think that must be a typo, the way I have it is the way it works. If You think about the way the wheels are pointing when toe is applied its easier to visualise what will be happening when cornering.

With Toe In the front of the wheel is pointing in towards the centre line of the car. When we are approaching a corner the inside wheel is effectively pointing in the opposite direction to the way we want to turn but the outside wheel is pointing the correct way.
We have to think about weight transfer and which wheel is more dominant on cornering during various cornering phases. When we turn the wheel to enter the corner the inside wheel is dominant, as we get further into the mid corner the weight shifts outwards and the outside wheel becomes dominant.
If we refer back to our Toe In car, when we make the initial turn in the dominant wheel is pointing in the wrong direction and therefore reducing our ability to turn, we need to increase our steering angle to suit and this slows us down. When we reach mid corner the outside wheel is already pointing into the corner and therefore we will require less steering angle and can hold onto our speed better.
The opposite is true of a Toe Out setup, when entering the corner our inside wheel is already pointing into the corner but when we reach mid corner our outside wheel requires more steering angle to follow the same line and therefore reduces grip and speed.

I'm told that camber can have a fairly dramatic effect on tyre wear but I haven't tested this yet myself so I'm afraid I have no useful information to hand. From what I can gather the effects are generally positive but I am unclear on the details.

@DolHaus

I applaud you on everything you have stated in your last few posts here. Everything you have stated here has been exactly as I have found it to be through my own testing. You are spot on as far as how the camber and toe settings work, exactly how I have also found them to be. I have done hours upon hours of testing and have come up with the same conclusions as you have as far as how camber now works. Its ironic, in a good way, that two people who have never collaborated together before as far as tuning theories go, come up with the exact same conclusions. In my opinion, that pretty much cements things for me as far as camber is concerned. As far as the LSD, I have always understood it to also work the way you have explained so that is really nothing new to me, but great job explaining it for those who do not know how it works. 👍 Great job you are doing here with this thread, you are truly an asset to the community. Keep up the great work my friend.

Thank you. I think the general problem with camber at the moment is that the basic setup criteria haven't yet been properly identified and accepted yet, at the moment everyone is sort of fumbling in the dark and running on the assumption that if it doesn't work immediately then it doesn't work at all. If you'd be up for some collaboration and sharing of thoughts and theories then I will always try to lend an ear and a second opinion

I'm not much for trusting... I will test myself when I get time, but I was rather hoping you were going to post some of the set ups/examples you have used to come to your conclusions.

There is no point in posting setups as without a direct comparator, that would be one sided information based on a particular drivers ability and style. My basic example is that if I want to use camber on the front wheels then I am going to need to add some degree of toe out to counter the initial understeer and make use of the increased potential mid corner grip. Thats all I'm saying.

Yes, of course decel effects rotation under braking... but the important (pronounced) effect is when you begin to release the brake pressure whilst trail braking... with ABS 1, the less brake pressure, the more decel affects the car, the more brake pressure, the less decel affects the car.

The harder you brake, the more load you are placing on the diff and the more effect the Decel setting will have. When you release the brake the size of the numerical gap between Decel/Initial becomes the dominant factor because you are going from the Decel phase to the Initial, the larger the gap the faster and more violent the transition will be. This can be a positive aspect if you want the car to react aggressively to input but it can also cause the drive wheels to overload the tyres and loose grip dramatically.
When trail braking (ie. Accelerating/Braking simultaneously) the diff will be using an average setting between the Decel and Accel setting. If you were using a setting of 5/20/10 for example, while trail braking your diff would be at roughly 15 for both if you were using equal amounts of throttle and brake. The overall setting would change dependant on the ratio of throttle/braking deployed.

I’m just confused by your interpretation of Initial...

If you set a low Initial and a high Accel the transition will be violent
If you set a high Initial and a high Accel the transition will be smooth

Then surely Initial affects the rate at which the diff takes up the input load?

It’s the only variable affecting the outcome!

Edit:

In relation to this point...

I was doing a bit more searching, and I noticed @Motor City Hami has a number of tunes in his garage running higher initial that accel.

MCH is one of the most respected and trusted tuners on the forum and a very decent driver, so you may want to check your assumptions?

All differential setting use load to determine how they work, the Initial is just a pre-load. It sets the basic characteristic in terms of how much potential differential rotation is possible in all functions. Any setting set below the Initial will have no aditional effect, it will default to the setting of the initial.

For example if I set my diff to 8/5/5 it will have exactly the same function as if I set it to 8/8/8. The accel/decel may be set lower to attempt to get a higher differential rotation ratio but because the Initial sets the baseline these figures are redundant.


Did you see Hamiltons crash in qualifying this weekend when his brake exploded? What basically happened was that the outside wheel could suddenly travel a whole lot faster than the inside wheel which caused a sudden weight shift resulting in a spin.
The same thing basically happens with a differential if you have a large gap between your Initial and accel/decel, you go from the wheel having resistive force to having none when you release the throttle/brake. The outside wheel suddenly speeds up and force does what force does best and switches to the path of least resistance which is now your outside wheel.
The larger the change in wheel speed between settings the more violent and less manageable the reaction. The function of the Initial in relation to the Accel/Decel is nothing more than reducing the amount of potential wheel speed change which smooths out the transition.

I don't really care that another tuner might be using settings contradictory to what I'm saying because what I'm saying is the truth. Hami might be a better driver (I wouldn't know as I've never raced him) and I truly respect his knowledge where suspension is concerned, I frequently refer to his guide when I'm looking for better explanations or more in depth analysis. His well deserved reputation as a tuner was gained in GT5 and his guide reflects that, but this is GT6 now, its a different game with different rules, some things are the same, others have changed.
As far as LSD's go, I am right up with the top dogs, nothing I say is based on assumption. There's a reason why the thread I wrote is a permanent feature in the tuning section of one of the biggest GT forums.

 

[BadgerVadge]

I usually can tune street cars to my style and do really good by myself. when i encounter a problem while test driving, I can quickly determine what is going wrong (in theory) by visualizing the suspension...it works for me.

My problem is race cars. I am attempting to make my first racecar tune without looking up on the GT6 tuning directory for guidance. The car is the new Nismo Team RJN GTR GT3 racecar...It is a magnificient tune stock! but once i added power it lost its finesse. I remember seeing the factory setup with the rear toe at +.60 and the front at -.45 IIRC (weird to me, but i dont know racecars yet!) ANYWAYS...
Here is my scenario - When I am accelerating full throttle on high speed turns on nurburgring, It seems like the front tires just stop trying to turn! In my head i keep thinking it has something to do with the rear downforce acting on the damping, or my toe setup.
I tried using more damping extension on the front tires (i think it might "push" out for more grip) but its not good still. I noticed that the factory setup had 1.5 deg. camber in front and 3.5 in rear...so i kept it like that for the balance? it seems okay around slower corners with a mild representation of the high speed understeer. ALSO when i am braking, the rear starts to wiggle on corner entry (I never use ABS or any aids)

What are your guy's thoughts on this? I am thinking its a toe issue, I havent setup toe for racing cars yet, its way different to me. what is a good reccomendation for the toe and should i tune it more extreme for racing soft tires compared to racing hard or keep it the same? i think i also read that stiff springs should have soft damping?

Thanks guys!

 

[Stotty]

There is no point in posting setups as without a direct comparator, that would be one sided information based on a particular drivers ability and style. My basic example is that if I want to use camber on the front wheels then I am going to need to add some degree of toe out to counter the initial understeer and make use of the increased potential mid corner grip. Thats all I'm saying.

I meant something like...

Take car X
Test with base tune (stock minus camber and toe)
Test with camber
Add toe until you get rid of the understeer
Does the car lap faster than with camber/toe at zero?

I haven't tested it like this, though I have tested camber on a car with toe. I will try to test it tonight.

Please don’t take this the wrong way, it’s a honest and open question... Have you done any specific testing (controlled using lap times/data logger), or are you posting theory at this stage?

The harder you brake, the more load you are placing on the diff and the more effect the Decel setting will have. When you release the brake the size of the numerical gap between Decel/Initial becomes the dominant factor because you are going from the Decel phase to the Initial, the larger the gap the faster and more violent the transition will be. This can be a positive aspect if you want the car to react aggressively to input but it can also cause the drive wheels to overload the tyres and loose grip dramatically.

That may very well be true, but when you brake hard (full brakes) ABS pretty much over rides the decel – you can brake very hard in a very unstable car with a low initial/decel, and still turn without spinning... it’s only as you start to bleed the brakes whilst still turning that the car becomes unstable – that’s the ‘stability control’ affect ABS has in GT6. As you ease the brake pressure, and the (unrealistic) stabilising effect of ABS reduces, an unstable car may rotate VERY aggressively if you don't have enough decel/+ve rear toe/front brake bias.... AKA brake release oversteer.

I agree that a car that rotates off the brakes/power is a good thing... providing one has the necessary skill to manage the resulting rotation!

When trail braking (ie. Accelerating/Braking simultaneously) the diff will be using an average setting between the Decel and Accel setting. If you were using a setting of 5/20/10 for example, while trail braking your diff would be at roughly 15 for both if you were using equal amounts of throttle and brake. The overall setting would change dependant on the ratio of throttle/braking deployed.

That’s not trail braking – trail braking is braking and turning simultaneously, gradually reducing brake pressure as you reach the apex (no throttle involved!). It’s used to maintain a forward weight transfer, increasing front grip on the entry phase of a corner.

What you’re describing is overlapping throttle and brake at the same time... which is actually a great technique in GT6 to manage weight transfer in unstable cars. It affects the car in the same way as a high decel (even when decel is at 5), without the negative effect of understeer. It seems to fool the physics engine in to thinking the weight is more stable and more centrally located!

Did you see Hamiltons crash in qualifying this weekend when his brake exploded? What basically happened was that the outside wheel could suddenly travel a whole lot faster than the inside wheel which caused a sudden weight shift resulting in a spin.

The same thing basically happens with a differential if you have a large gap between your Initial and accel/decel, you go from the wheel having resistive force to having none when you release the throttle/brake. The outside wheel suddenly speeds up and force does what force does best and switches to the path of least resistance which is now your outside wheel.

Yes, I saw it. The last information I saw on that was it was caused by front right brake failure?

I don't really care that another tuner might be using settings contradictory to what I'm saying because what I'm saying is the truth. Hami might be a better driver (I wouldn't know as I've never raced him) and I truly respect his knowledge where suspension is concerned, I frequently refer to his guide when I'm looking for better explanations or more in depth analysis. His well deserved reputation as a tuner was gained in GT5 and his guide reflects that, but this is GT6 now, its a different game with different rules, some things are the same, others have changed.

As far as LSD's go, I am right up with the top dogs, nothing I say is based on assumption. There's a reason why the thread I wrote is a permanent feature in the tuning section of one of the biggest GT forums.

That’s a very bold and confident claim

If you’re that good a tuner, come build something for the Seasonal time trials – let Crank/Ramon/Raja/Doodle run it (consistently at the top of the Global rankings) and see how they get on.

The current GSX-R at Bathurst is a good one – the car reacts to quite small changes, so it should be a good guide to your ability to build a fast car.

 

[Stotty]

Camber test results...

I used the BMW M3 CSL as it's a car I've driven a bit previously, and it has a very good balance for a FR. Very little understeer, loads of rotation. reasonably quick, and easy to drive. Left the tyres as SH to reduce the effect of having to manage the throttle on exits (the CSL has almost perfect traction on SH).

G27, Gteye brake mod.

Track was Suzi East as I know it very well, it has a good variety of corners and it's a short lap, so easy to test on.

I bought a new car from the dealership, added fully custom suspension (no other parts), and set camber and toe to 0 f & r to get a base lap time.

No aids other than ABS 1... easier to be consistent with ABS, and this has no effect on the car once the braking phase is over. Grip real (not that this has much effect off line).

10 laps on each test, focusing on the effect of camber and toe on the front. In all instances, was running within 0.2s of fastest lap consistently by lap 7 of each session.

1. 0 front camber, 0.00 front toe
Lap time: 53.884
Car feels very pointy. No understeer. Lots of rotation... almost too much in turn 1/2.

2. 1.0 front camber, 0.00 front toe
Lap time: 53.642
Car feels a lot easier to drive. More understeer. Less rotation in to turn 1/2 and when throttle is eased.

3. 1.0 front camber, -0.05 front toe
Lap time 53.516
Car feels slightly better. Slightly less understeer. Less rotation when throttle is eased.

4. 1.0 front camber, -0.10 front toe
Lap time: 53.566
Feels even more stable. Understeer increasing mid corner & exit. Less rotation when throttle is eased.

5. 1.0 front camber, -0.15 front toe
Lap time 53.528
More stable. More understeer. Overcome by turning in earlier. Early turn-in compromises exit speed. Less rotation when throttle is eased.

6. 0 front camber, -0.15 front toe
Lap time 53.526
Good turn in. Loses mid corner grip. Regains grip mid corner to exit suddenly when power is eased to manage understeer.

7. 0 front camber, -0.10 front toe
Lap time: 53.353
Turn in slightly less sharp. Mid corner adjustability better.

8. 0 front camber, -0.05 front toe
Lap time: 53.535
Turn in smoother. More rotation when throttle is eased to adjust balance. Less mid corner understeer. Much better exit.

At this stage, I go back to the stock set up as familiarity with the car track naturally leads to lap time improvement. I also re-run the fastest combination of camber/toe from the original test.

9. 0 front camber, 0.00 front toe
Lap time 53.202 (had a lap 0.190 faster than this at T2, but ran wide in the final corner)
Now I'm more used to the car the rotation is much more manageable. Turn in is smoother. More rotation. Less mid corner understeer. More adjustable balance on small throttle changes mid corner.

10. 1.0 front camber, -0.05 front toe
Lap time: 53.432
Increased understeer. Need to turn in earlier to compensate, compromising exit.

Conclusions
On a car with a neutral balance, and plenty of rotation, adding camber and then toe (incrementally) makes the car progressively understeer and also makes it easier to drive - cars that understeer are generally easier to drive. BUT the increased understeer requires an earlier turn in and compromises exit speed, and also reduces the fine adjustability of the car mid corner. Effect would be magnified with less grippy tyres.

Comments
I can understand how someone might add camber and improve their lap times if they prefer a car with less rotation. But if you can handle the rotation, lap times are faster with no camber/toe as there's less understeer so you can run better lines.

 

[turismoslayer]

Gentlemen, sorry to pry in to your conversation but you mention an initial diff setting close to accel/decel being a smoother transition, and an initial setting far a part from accel/decel (I presume initial would be very low and accel/decel high) being a violent or harsh and faster transition. Either way I think both are fast transitions. The diff corresponds accordingly to accel/decel whether the initial is close or not, right?

I'm trying to wrap my head around this and I think I got it. Or maybe not. I imagine a damper/spring, high spring rate and high damper settings, very stiff and not much movement. Almost like a diff with close settings, not much transition. How about a loose damper/spring set up, more movement. High difference with initial and accel/decel, very noticeable harsh and violent transitions. No?

 

[Stotty]

Gentlemen, sorry to pry in to your conversation but you mention an initial diff setting close to accel/decel being a smoother transition, and an initial setting far a part from accel/decel (I presume initial would be very low and accel/decel high) being a violent or harsh and faster transition. Either way I think both are fast transitions. The diff corresponds accordingly to accel/decel whether the initial is close or not, right?

I'm trying to wrap my head around this and I think I got it. Or maybe not. I imagine a damper/spring, high spring rate and high damper settings, very stiff and not much movement. Almost like a diff with close settings, not much transition. How about a loose damper/spring set up, more movement. High difference with initial and accel/decel, very noticeable harsh and violent transitions. No?

Fun, isn't it

Yes, that's exactly how I see it, and why I'd typically have diffs at 5, X, 5.... though X isn't normally a big number as this causes exit oversteer.

I want the car to transition as quickly as possible (well, as quickly as my reactions can manage ).. this makes for a car that turns in and changes direction quickly, a car that will 'tuck' when the power is eased fractionally mid corner to get the nose back on line... but it also needs to be stable enough to handle my level of steering inputs and my level of braking inputs.

The better your reactions & steering/throttle/braking inputs, the more rotation you can manage and the faster you'll be.

 

[turismoslayer]

@Stotty, I gather that your driving style can be described as abrasive. I'd like to try one of your tunes sometime. I find myself to be more on the safe side as of late. Before I used to be more aggressive but now realizing that aggressive can be good at times. If I can manage to balance smooth inputs with being aggressive at the same time I will be golden. Right now, threshold braking is where I'm trying to increase skill then go from there. I guess I'm still finding out what kind of driver I am.

 

[DolHaus]

I meant something like...

Take car X
Test with base tune (stock minus camber and toe)
Test with camber
Add toe until you get rid of the understeer
Does the car lap faster than with camber/toe at zero?

I haven't tested it like this, though I have tested camber on a car with toe. I will try to test it tonight.

Please don’t take this the wrong way, it’s a honest and open question... Have you done any specific testing (controlled using lap times/data logger), or are you posting theory at this stage?

I am currently trying to do some detailed testing on camber but I am struggling for game time and progress is slow as a result. My results are pointing me in the direction that camber could definitely hold improvements but like every other tuning option it is a case of gain vs. loss.
By itself it can make small improvements at various angles when combined with Toe Out both in terms of fastest lap and average time (to determine stability for race cars). I believe that the positive aspects of camber (increased ability to sustain high load during cornering) could be greatly enhanced when combined with other suspension adjustments.
Other aspects such as the ratio of front and rear camber settings can also make a noticeable change to the basic handling characteristics of a car so this can be used to tame wild cars or put a bit of life into overly stable cars, this aspect is important because not every car is meant to win races but people still want to try and this offers them that ability.
I cannot say with 100% certainty that camber will always lead to improvements in every single instance, that would be like saying making your springs stiffer will make you faster, it will work on some cars/tracks/tyres, it won't on others. Thats just the way tuning is in GT6, there aren't any truly concrete answers apart from having more power will make you go faster in a straight line.

That may very well be true, but when you brake hard (full brakes) ABS pretty much over rides the decel – you can brake very hard in a very unstable car with a low initial/decel, and still turn without spinning... it’s only as you start to bleed the brakes whilst still turning that the car becomes unstable – that’s the ‘stability control’ affect ABS has in GT6. As you ease the brake pressure, and the (unrealistic) stabilising effect of ABS reduces, an unstable car may rotate VERY aggressively if you don't have enough decel/+ve rear toe/front brake bias.... AKA brake release oversteer.

I agree that a car that rotates off the brakes/power is a good thing... providing one has the necessary skill to manage the resulting rotation!

As I have said previously I would alter the settings to suit the needs of the situation, I might use more or less decel to suit how effective the settings felt, there is no concrete rule or a best setting. You might struggle to spin during braking even with the decel set at 5 on some cars with ABS1 but it is more than possible with others. Generally mid/rear engined cars with significant rear weight distribution on sport or comfort tyres are the likely suspects, these can very easily overcome the rear tyres under braking.
You can definitely lock the rear brakes with ABS1, it will try to stop you from locking up but once they lock they don't unlock until you release the brakes. I use ABS 1 when I drift and I tend to use the foot brake rather than the handbrake for slowing and getting the car rotated in tight switch backs. I do not need to make any special bias adjustments to do this either.
For this reason the decel setting is important in controlling entry rotation regardless of ABS setting. When set at 5 for initial/decel the problems encountered when releasing the weight are the result of uncontrolled weight transfer. This can be potentially caused by incorrect brake bias/unsuitable ride height/springs/dampers/weight distribution/ settings and further compounded by the lack of resistance from the wheels caused by low differential settings. If the decel setting is significantly higher than the initial then effect is increased due to the larger transition. This lack of resistance can be both a positive or a negative aspect dependant on the demands of the situation. Saying that it is overridden by ABS1 is frankly rediculous, the effect may be reduced exponentially by increasing ABS strength but there is still an effect to be tuned.



I think what is winding me up is that you are not really here to learn anything but here instead to prove that your such a good driver that you don't need my tuning advice. Every time I explain how something works and how it could potentially be used to gain performance you just say something to the effect of "maybe if you were a better driver like me you'd understand what I was talking about and why you're wrong". I don't know if this is just the way you talk or what, but you seem to be trying to talk down to me constantly and it really irritates me. I think it may be best if we just agree to disagree and move on.

Thank you for your data though, it appears fairly similar to my own first pass tests using a balanced FR car at a single circuit. I have discovered by repeating tests multiple times and by using multiple sources and averages you get more accurate results, the first pass doesn't really tell you anything except that we need B-Spec Bob back to get concrete data.

Gentlemen, sorry to pry in to your conversation but you mention an initial diff setting close to accel/decel being a smoother transition, and an initial setting far a part from accel/decel (I presume initial would be very low and accel/decel high) being a violent or harsh and faster transition. Either way I think both are fast transitions. The diff corresponds accordingly to accel/decel whether the initial is close or not, right?

I'm trying to wrap my head around this and I think I got it. Or maybe not. I imagine a damper/spring, high spring rate and high damper settings, very stiff and not much movement. Almost like a diff with close settings, not much transition. How about a loose damper/spring set up, more movement. High difference with initial and accel/decel, very noticeable harsh and violent transitions. No?

You are indeed correct, the larger the gap between the Initial and the Accel/Decel the more aggressive the transition between functions will be.

To use your suspension analogy:-
A low Initial - high Accel/Decel would be like a soft spring/damper combo in that energy can shift around unimpeded when force is applied. Useful in some situations but lethal in others.
Increasing the Initial would be like stiffening the springs because it has an overall effect. Lowering the Accel/Decel would be like adjusting the dampers because it is more refined/focussed in its approach 👍

 

[FSportIS]

Now, this is the AWESOME! I understand LSD a whole lot more with this post than any other guide lol. You explained this really well especially the relationship among initial/acer/decel. It is not simply as increase this, you get this effect or increase that to get that effect. It rather works holistically like a whole system like you mentioned.

At this point he closest I can give to an answer is that the more camber you run, the more Toe Out you need to run to correct the cars alignment. Adding camber is having a similar effect to Toe In, you get more mid corner grip but your initial turn in is less sharp. To combat this we use toe out to regain the initial turn in and sharpness. We can basically have the best of both worlds rather that being the best compromise.

1.0 Front camber = -0.18 Front toe
2.0 Front camber = -0.40 Front toe



None of that is real life theory, its all in game stuff.

Initial is the baseline setting and what is acting upon the the drive wheels while rolling without brake or throttle applied.

Accel/Decel are separate settings from the Initial, when you are on the gas you are in the Accel phase, when you are on the brakes you are in the Decel phase.

All the numbers represent is how much speed differential there can potentially be between the drive wheels.
A lower number means there can be a greater speed differential and therefore axis rotation is more easy (the outside wheel travels further round a corner than the inside and therefore needs to rotate faster).
A higher number means that the wheels travel at a more similar speed which makes them resist axis rotation and even cause outside wheel slip in extreme cases.

Here is a simple test for any LSD setting:-

First we will test Initial on a RWD car

Pick a corner
Set your Initial to 5
Drive into that corner and lift off the throttle
Turn into the corner while still off the throttle and note how responsive and easy to turn in the car was
Set your Initial to 30
Drive into that corner and lift off the throttle
Turn into the corner while still off the throttle and note how responsive and easy to turn in the car was

You will find that the car understeers a lot more and feels like the rear is way more reluctant to rotate. This is because the diff is preventing the outside wheel from turning at the higher speed it require to make the turn without slipping.


Next we will test Accel on a RWD car

Pick a corner
Set your Accel to 10
Turn into the corner and line up your exit, nail the throttle and note how much rotation is possible on exit
Set your Accel to 30
Turn into the corner and line up your exit, nail the throttle and note how much rotation is possible on exit

You will find that the car pushes wider and wider as you increase the accel value for the same reason as above.


I'm sure you can figure out how to do decel on your own.


The relationship between Initial and Accel/Decel is very important because of the way it can affect the car during various phases.

Lets imagine that you have your 5/20/5 settings and you are going round a long sweeping bend at 100mph. I will use some percentages to illustrate the point but these should not be taken as fact.

Lets say that when set to 5 the outside wheel can spin 100% faster than the inside
When set to 20 the outside wheel can spin 50% faster than the inside.

You are going round the corner at full throttle and the Diff is in the Accel phase. Your inside wheel is spinning at 100mph and your outside wheel is spinning at 150mph.
You notice the car is starting to drift wide so you decide to lift off the throttle in order to get the nose pointed back in. When you lift off the throttle and the Diff enters the Initial phase, this means that the inside wheel is still spinning at 100mph but your outside wheel can now spin at up to 200mph.
This sudden change in speed unbalances the car and allows the car to over-rotate leading to instability and probably a spin.

The larger the gap between Accel/Decel and Initial, the more pronounced the effect will be when switching between phases. If it is too high then the transition will cause a load spike and overcome the tyres leading to a complete loss of grip.

You can get reasonable results by using 'base' settings but you will get way better results if you actually spend time working out how the diff is affecting the drive wheels and how it could be improved. If you want to be fast then you've got to understand how your power is getting from the engine to the wheels, its one of the most dominant and key features on any car and should be treated as a high priority component.

 

[DolHaus]

Now, this is the AWESOME! I understand LSD a whole lot more with this post than any other guide lol. You explained this really well especially the relationship among initial/acer/decel. It is not simply as increase this, you get this effect or increase that to get that effect. It rather works holistically like a whole system like you mentioned.

Thank you, I'm glad you understood and learned something from it 👍

 

[rams1de]

I don't know why but I'm always compelled to read these tuning arguments despite the fact only a small proportion of the verbiage relates to GT6.

Hopefully it's just a rush of blood from typing walls of text, but what got into your head to write this?

As far as LSD's go, I am right up with the top dogs, nothing I say is based on assumption. There's a reason why the thread I wrote is a permanent feature in the tuning section of one of the biggest GT forums.

Surely your not implying this thread is stickied in recognition of your ability or knowledge of tuning in GT6?

From the outset it has contained erroneous guidance which would have been a hindrance rather than help to prospective tuners.

'Top dog' - I nearly spat my coffee

 

[DolHaus]

I don't know why but I'm always compelled to read these tuning arguments despite the fact only a small proportion of the verbiage relates to GT6.

Hopefully it's just a rush of blood from typing walls of text, but what got into your head to write this?



Surely your not implying this thread is stickied in recognition of your ability or knowledge of tuning in GT6?

From the outset it has contained erroneous guidance which would have been a hindrance rather than help to prospective tuners.

'Top dog' - I nearly spat my coffee

I'm not sure if you are being sarcastic or what?
If not, what erroneous guidance would you be referring to?
As far as LSD tuning goes I would consider myself up there with the best, my suspension tuning could do with some refining at times and transmissions are still confusing to me but I'm not a boastful person by a long shot so I would not say such a thing if I couldn't back it up.

 

[rams1de]

I'm not sure if you are being sarcastic or what?
If not, what erroneous guidance would you be referring to?
As far as LSD tuning goes I would consider myself up there with the best, my suspension tuning could do with some refining at times and transmissions are still confusing to me but I'm not a boastful person by a long shot so I would not say such a thing if I couldn't back it up.

No, I wasn't trying to be sarcastic but probably didn't do a good job of keeping it light-hearted. My apologies if it came over that way.

I assumed you'd be able to remember the original descriptions posted in the guide which explained ride height working opposite to the way it does in GT6. Similarly your description of camber was totally incorrect and failed to identify the loss of grip produced. Also, the description for toe settings was wrong with negative and positive toe reversed.

Take a look back over the thread, although the guide is more accurate now the evidence is there among posts from other members and subsequent edits. It took months for the suspension guide to resemble what tuners had discovered in the first couple of weeks after the game's release.

One thing that struck me when this thread went up, was that you couldn't have done any testing and in playing the game were not identifying important aspects of the game's tuning parameters. I'm not referring to the finer elements of tuning that may or may not find hundreds of a second and which can be difficult to discern but to settings that have a significant and easily identifiable impact, not only on the balance of a tune but on lap times too.

I hadn't considered your previous posts as boastful which was possibly why the quoted statement jumped out as extraordinary. But as far as I can see, your Top Dog status is self-appointed and the suggestion that this thread was stickied because of your tuning knowledge is somewhat hollow given the history of the thread.

 

[DolHaus]

I usually can tune street cars to my style and do really good by myself. when i encounter a problem while test driving, I can quickly determine what is going wrong (in theory) by visualizing the suspension...it works for me.

My problem is race cars. I am attempting to make my first racecar tune without looking up on the GT6 tuning directory for guidance. The car is the new Nismo Team RJN GTR GT3 racecar...It is a magnificient tune stock! but once i added power it lost its finesse. I remember seeing the factory setup with the rear toe at +.60 and the front at -.45 IIRC (weird to me, but i dont know racecars yet!) ANYWAYS...
Here is my scenario - When I am accelerating full throttle on high speed turns on nurburgring, It seems like the front tires just stop trying to turn! In my head i keep thinking it has something to do with the rear downforce acting on the damping, or my toe setup.
I tried using more damping extension on the front tires (i think it might "push" out for more grip) but its not good still. I noticed that the factory setup had 1.5 deg. camber in front and 3.5 in rear...so i kept it like that for the balance? it seems okay around slower corners with a mild representation of the high speed understeer. ALSO when i am braking, the rear starts to wiggle on corner entry (I never use ABS or any aids)

What are your guy's thoughts on this? I am thinking its a toe issue, I havent setup toe for racing cars yet, its way different to me. what is a good reccomendation for the toe and should i tune it more extreme for racing soft tires compared to racing hard or keep it the same? i think i also read that stiff springs should have soft damping?

Thanks guys!

If you are encountering front end grip loss at high speed then my first port of call would be to check the levels of downforce on the front and rear, it sounds like the faster you are going the less balanced the car is becoming. What might be happening is that the rear downforce is too high in relation to the front and the front end doesn't have enough weight over it to do anything. Basically the faster you go the more the rear is pushing down and the front is lifting. To solve this I would either reduce rear downforce or increase front downforce to rebalance the car at speed. Another solution to the same problem is to put some ballast in the front of the car to achieve the same goal in terms of adjusting the balance.

If this doesn't solve the problem then I would look at the LSD Accel setting, try lowering this a few clicks and see if that makes the difference, it could just be that your outside wheel is just not able to spin fast enough to allow you to maintain the desired arc.

The front Toe could be a little bit too extreme also and causing loss off grip in mid to late corner settings and the rear Toe could be providing too much resistance.
The front toe is running a lot of Toe Out (-) to suit the camber but it might be set a little strong so try reducing this in increments of 5 until you start to get your mid turn grip back but not so much that the car becomes unresponsive. Do the adjustments in increments until you find the two rough settings that best suit your needs, then you can further refine it by single digits until you find perfection, this is generally the most efficient way of refining your search.
The rear Toe might be preventing you from rotating properly as well so start to reduce the number until you find the sweet spot. In the last update GT changed the standard rear toe figure from 0.20 up to 0.60, I believe this was done to stabilise some of the more unpredictable cars in standard form but it has made most normal cars overly stable as a result. I generally knock it back down to the original 0.20 setting as a starting point before making adjustments.

When thinking about dampers we need to think about what they are doing and what the numbers mean. The dampers are connected to the springs, they can only resist the forces acting on them rather than adding anything to them. The compression settings define how quickly the spring can react to compressive forces, the higher the number the slower the spring will compress, the lower the number the faster and more naturally the spring reacts.
The extension setting is basically the same except it controls how fast the spring extends after compression. The higher the number, the slower the spring will recoil, the lower the number the faster and more forcefully the spring will extend.
To illustrate the process in action we will imagine a car braking whilst approaching a corner. When we brake the weight wants to continue going forward so the majority of it ends up over the front suspension, the springs will compress under the extra load in order to dissipate the energy.
While this is happening it is easy to see what each of the dampers job is, the front end is in the compression phase and the rear is in the extension phase. To control this we need the front damper compression to be strong enough to stop the car dipping its nose violently but also compliant enough to allow a controlled amount of weight transfer. The rear damper extension will do a similar job only in reverse, it needs to be strong enough to slow the forward weight transfer but soft enough to allow it to happen.
When we release the brakes the opposite process happens as the car attempts to rebalance itself, the rear will compress and the front will extend. Now we are looking at the front extension rate and the rear compression rate and doing the exact same process but keeping in mind that the process will be less extreme than in the braking phase as there is less energy being transferred.

 

[DolHaus]

No, I wasn't trying to be sarcastic but probably didn't do a good job of keeping it light-hearted. My apologies if it came over that way.

I assumed you'd be able to remember the original descriptions posted in the guide which explained ride height working opposite to the way it does in GT6. Similarly your description of camber was totally incorrect and failed to identify the loss of grip produced. Also, the description for toe settings was wrong with negative and positive toe reversed.

Take a look back over the thread, although the guide is more accurate now the evidence is there among posts from other members and subsequent edits. It took months for the suspension guide to resemble what tuners had discovered in the first couple of weeks after the game's release.

One thing that struck me when this thread went up, was that you couldn't have done any testing and in playing the game were not identifying important aspects of the game's tuning parameters. I'm not referring to the finer elements of tuning that may or may not find hundreds of a second and which can be difficult to discern but to settings that have a significant and easily identifiable impact, not only on the balance of a tune but on lap times too.

I hadn't considered your previous posts as boastful which was possibly why the quoted statement jumped out as extraordinary. But as far as I can see, your Top Dog status is self-appointed and the suggestion that this thread was stickied because of your tuning knowledge is somewhat hollow given the history of the thread.

I don't know if you've ever tried to write a guide to something that can be useful to both complete beginners that have no understanding of mechanics and to those who know how to make a car fast but would like to further their knowledge, but i'll tell you that its not easy. Mistakes will be made and I try my hardest to fix them if they are factually wrong rather than just being different to someone's opinion. A lot of the information in the early stages was transferred over from GT5 where I had plenty of experience and knowledge but needed to be slightly edited to fit the newer physics in GT6, I have tried to update as I have become aware of changes but it is impossible for me to be ahead of the curve because I'm not a programmer and I didn't create the physics engine.
The whole game is a learning experience and comes down to figuring out what tuning principals are present and how they are represented, its a complicated business trying to find the truth in what is a very subtle and complicated tuning model.

As for the top dog thing, I apologise for losing my temper and making boastful statements. I do not feel the statement to be untrue as one of the comments that comes up time and again when my cars are put under public scrutiny is how good the diff feels and the effect it has on the balance of the car, these are comments from the top tuners and therefore have credence. I also do reasonably well in contests relative to the amount of time spent on my entry, if I chuck in a rough and ready car because real life has left me short on playing time then I usually do well in drivers choice but end up in the mid pack in terms of pace, if I put a full effort in then I am right up around the podium positions on both accounts.

The thing that kind of irks me is that you neither post tunes nor enter contests in this forum, this means that we have no actual gauge on your own performance. You rarely offer any sort of positive input to physics discussions and spend your time instead dismissing others. For these reasons I must respectfully dismiss any further criticism from yourself, when you prove yourself on the track and in the forums then I will have more patience but for now you are just another guy on the internet who likes to complain.

I am sick of this, I am only trying to help and all I get in return is more trouble.
If you think you can do a better job then I encourage you to prove it. Seriously, if I thought there was a better general guide available then I would ask the mods to close this thread in a heartbeat.

 

[FSportIS]

Sorry to jump in the conversation. In my opinion, I think EVERYONE including both beginners and pros LEARN on a continuing basis and during that process, mistakes/errors occur inevitably. That is totally NORMAL.

The following are important:
1. Recognize the mistakes. Lots of people are good at this.
2. Admit that we make mistakes. This takes a whole lot of courage.
3. Correct the mistakes.
4. Do not repeat the same mistake.

Not only has DolHaus just gone through that process, he has continued refining the tuning guide which is very helpful to the community. He should deserve some credit for that.

Also, it is not polite to pinpoint someone else mistake publicly in a manner that would provoke a verbal war. I'm very disappointed to see this happening in various forums. What I would suggest is that people should hold off their ego first before they start to make any statements that might provoke a verbal war. Instead, they should all focus on the very topics of discussion itself by minimizing any reference that may seem personal to either side.

Last but not least, phrases like "I'm the badazzz top dog best of the best mofo", "you are wrong!!!!", sarcastic remarks that carry some personal attack etc should be avoided because that can easily provoke an unnecessary verbal war. Keep the ego in check and focus on the discussion.

Peace

 

[rams1de]

@DolHaus I'm not going to pick over your last post. I'm not interested in getting into an argument and only replied last time to answer your question.

My posting history is quite small, less than 200 posts, so it's easy to see where and when I've contributed to discussions with my personal experiences and a little bit of data. I doubt you'll find many dismissive posts among them.

As far as tuning and FITT goes, I'd love to get involved but don't have the time. If I did it would be as a driver (not that I'm any good) as there's plenty of tuners already. I would never lay claim to being a great tuner but I do like to make my own set ups and I mostly tune for specific regs at the club I race with and I change them quite a bit from track to track.

I've have posted a couple of tunes here on GTP, one in the Stratos Difficult Car thread and another quick tune I did for the SSR5 seasonal which I thought would be worth storing for future use and could be useful for others.

Set ups are such a personal thing, due to driver ability, style, controller etc, there's nothing new I can bring to the party. When I discovered the issues with ride height and camber in December I came straight over here only to find it was old news but I did share my findings in one of the early tuning threads.

For my club mates at GBRC who are pressed for time, I've been preparing some base setups and a guide on how to adapt them to suit personal style. If you're interested you can find them here at GTArena.

I've no axe to grind, honest, you're more than welcome to join us for the racing which is clean and good fun. There's some pretty good drivers there but well short of the standard you find topping the TT leaderboards on PSN.

 

[DolHaus]

@rams1de Looks like a fun group of cars, might well take you up on that if I can find the time 👍
I apologise for losing my temper, recent events have put me a little on edge and my patience has disappeared as a result. I'm more than happy to bury the hatchet and move on