LSD Settings: How they really work in GT5?

[No_OBsT33R]

So your experience with LSDs is from seeing them on a table in mechanics school. Ever race? Ever tune one for your race car? Ever drive a car with a welded diff? A clutch type? A spring and block pressure plate diff? A torsion? I have.

You are claiming to have it all figured out. You state that your thoery follows the in-game descriptions, yet you distort how accel is described in the game. I think you are having a difficult time explaining your thoery to everyone, not because we are all on some lower level of engineering understanding, but because you haven't really worked out your thoery. You don't even get how weight distribution affects an LSD and what you can do to the settings. Your knowledge from seeing them sitting on a bench and from reading an artile on how stuff works, hardly gives you the credibility to tell others that your thoery is fact.

Actual I do have track experience, while I will not go into detail (as it's irrelevant the principles are what's important) quite a bit actually. My only experience is far from just on the table, and I only suggest you and others go read the info on how stuff works or take a mechanics class, but the article seems more realistic

I understand how weight works, but you misunderstand the fundamental principles at play, & while weight will impact the tires ability to grip and therefore how much power it can handle (hint hint) the LSD doesn't care, it only sees the end result. With the outside wheels loaded, gripped up to hell, the LSD still sees the outside wheel rotating faster & the inside slower. Closer to lock the more power the inside wheel retains (and as stated by the game "the more pronounced understeer will be". It will make the car harder to turn, it also states "increasing the sensitivity combats oversteer".meaning it will reduce throttle oversteer (throttle oversteer is when too much power goes to the outside wheel and it over-rotates its turn radius) it's all confirmed in the game.

Sooo

Get over it.

 

[Will27]

Closer to lock the more power the inside wheel retains

This is where we disagree.

If your diff is open under acceleration, you will spin the inside wheel.

The path of least resistance (Edit -)under acceleration is the wheel with significantly less grip, not the one that's rotating faster.

 

[Adrenaline]

Fight fire with fire... Let's see how you act, when arguing with yourself.

Actual I do have track experience, while I will not go into detail (as it's irrelevant the principles are what's important) quite a bit actually. My only experience is far from just on the table, and I only suggest you and others go read the info on how stuff works or take a mechanics class, but the article seems more realistic.

I do this for real, what do you do?

Your reviews are always opinionated and make technical critiques. You seem to hold high value in your own opinion, but Just so I know where you're coming from;

What's your automotive background?

Where do you get your info?

I'm curious because you say one thing is high or another is low, constantly criticizing (possibly a size complex issue) but I need to know, is this your opinion based on theory, video game playing, & google? Or Do you have any real world automotive expertise?

What car do you Drive?

NOTE to Adrenalin
Any of those credentials yet? Or you ignoring(avoiding) the question? If your going to be so critical, and out right tell people their methods are right or wrong, please inform us where your knowledge comes from. Info is only as good as the source. If the source is unknown it's worthless as I don't know if your an Ayrton Senna class driver (well....) or some nerd who never drove a track in his life, or even came close to tuning cars..,

Closer to lock the more power the inside wheel retains (and as stated by the game "the more pronounced understeer will be". It will make the car harder to turn, it also states "increasing the sensitivity combats oversteer".meaning it will reduce throttle oversteer (throttle oversteer is when too much power goes to the outside wheel and it over-rotates its turn radius) it's all confirmed in the game.

I don't suppose you ever considered the possibility that oversteer and throttle oversteer are 2 different things?

 

[Motor City Hami]

This is where we disagree.

If your diff is open under acceleration, you will spin the inside wheel.

The path of least resistance (Edit -)under acceleration is the wheel with significantly less grip, not the one that's rotating faster.

+1

Noobster can only see what he learned by looking at an LSD on a bench. He believes that the inside tire and outside tire must always follow differing numbers of rotations in a corner (say inside goes shorter distance and makes 10 rotations and outside goes longer and makes 15 rotations). He is leaving out that the inside tire can in fact do extra rotations by slipping on the pavement as would happen with a welded or fully locked diff. In cars where enough weight is unloaded from the inside tire, this slipping won't have much affect on mid corner speed. Porsche used locked diffs for some 30 years in racing, yet Noobster wants to argue that two tires MUST always rotate a different number of times - well, because - when you roll a cup around a table in auto shop class, it demonstrates his thoery.

 

[FlyinHawaiian77]

I for one would just like to say thank you for all the hard work you are putting into the game and then sharing it with us. I've been using your method for quite a while now and it works for me all the time.

 

[No_OBsT33R]

This is where we disagree.

If your diff is open under acceleration, you will spin the inside wheel.

The path of least resistance (Edit -)under acceleration is the wheel with significantly less grip, not the one that's rotating faster.

No open diff slips the inside wheel (as in sends power to the outside wheel it wont spin the inside wheel) A locked diff will force the inside wheel to keep rotating speed, spinning it if it's path line is too small) you got it backwards. Could you really imagine a car that forced the inside wheel to rotate more then the outside wheel in a turn, its not ideal.

Your basically confusing at the wheel and at the LSD. The grip is increased or decreased at the wheel and the LSD only sees the final result (the difference in wheel speed one side to the other) it doesn't see what's causing that difference, it only sees the difference and acts on that.

+1

Noobster can only see what he learned by looking at an LSD on a bench. He believes that the inside tire and outside tire must always follow differing numbers of rotations in a corner (say inside goes shorter distance and makes 10 rotations and outside goes longer and makes 15 rotations). He is leaving out that the inside tire can in fact do extra rotations by slipping on the pavement as would happen with a welded or fully locked diff. In cars where enough weight is unloaded from the inside tire, this slipping won't have much affect on mid corner speed. Porsche used locked diffs for some 30 years in racing, yet Noobster wants to argue that two tires MUST always rotate a different number of times - well, because - when you roll a cup around a table in auto shop class, it demonstrates his thoery.

if you don't know, you don't know. If your confused, your confused. C'est la Vie. I can only show you what's right, I can't force anybody to accept it.

Open diffs the Slow wheel sends power to fast wheel, if the slow wheel is slowed to a stop (more resistance then the moving outside wheel) it will send 100% power to the outside wheel. This allows a car to take a turn WITHOUT FORCING the inside tire to slip. On a Locked diff Yes the inside tire can slip and the car will make the turn, but this is not good, we want to corner without slipping the tires and waisting tire tread and over stressing the suspension and axles. Don't confuse "possible" with Ideal. It's possible to drive around with a locked diff, it's FAR from ideal.

Porsche were also making fundamentally flawed cars for 30 some years, big surprise they made compromises to accommodate those flaws. It's funny because if they had been using the GT5 LSD they would be increasing the accel (bringing the diff closer to lock) to deal with the cars issues with throttle oversteer. This falls perfectly into my explanations, and is a great example, Thanks

You guys argue things you do not fully understand, it's one thing to have an idea of how something works, it's another to have a comprehensive understanding. I ONLY say this because when you do know, you can spot the misunderstandings. If you misunderstand you won't see it.

 

[chuyler1]

I think this discussion needs to end until someone posts a video showing an open diff and a closed diff on a turn.

No_OBsT33R is arguing that with an open diff (5/5/5)*, the outside tire will lose traction first because it is "spinning faster". Everyone else appears to believe the inside tire will lose traction first because it has less traction to begin with. Do not confuse open diff with closed diff, as the opposite is true when a welded diff is used (60/60/60)*.


Until we get past that, this is just a flame war.

* I am aware that these settings are not completely open and closed, but they are as close as the game will get.

 

[No_OBsT33R]

It may be people are confusing things with a fully open diff. An adjustable LSD is a tool to find a middle between a fully open diff and a locked diff.

Fully locked both wheels retain 50% to each side power at all times.

Fully open diff sends 50% to each side until it slips, when slipping the amount of resistance reduces the power put down to accommodate the slower wheel, it retains only the amount of power to deal with the slower wheel. Let's say the inside wheel can only handle 25% power, that is transferred to the outside and the outside is forced to only use 25%. So the inside wheel retains 25% power and it's transferred to the outside wheel, so we have 25/25. If we go extreme but not all the way. 1% of power can be retained, it's then transferred to the outside wheel and we get 1/1. Reducing and reducing the power moving the car forward to deal with the resistance on the inside wheel.

A fully locked diff splits power 50/50 all the time. That's it, that's all. As the inside Line is smaller then the outside, the tire slips.

An adjustable LSD allows us to run 50/50 going straight, then in a turn where the inside wheel needs 25% due to the smaller radius (the open diff would use 25/25, the locked diff would use 50/50) but A hypothetical LSD in the middle of 25/25 & 50/50 would be 37.5/37.5. A hypothetical increase bringing us closer to lock brings us to 40/40. The inside wheels retains more power it is transferred to the outside, we keep moving forward. The closer to diff lock we go, the more power is put down by the inside (yes the outside too, but it's the inside that will be overpowering it's turn radius) a hypothetical decrease will bring us to 35/35. The inside wheel retains less power, less is transferred. Higher from the amount that would be applied with a fully open diff the ideal point is above what the tire needs before passing the tires threshold of grip.

It's then the int / accel / Deccel we use to manipulate the power being put down.

Int low is a loose free turning car (potential oversteer)

Int high is a tight harder to turn car (potential understeer)

Accel high is potential roasting of the inside tire, combats throttle oversteer (potential understeer)

Accel low reduces acceleration force (potential oversteer)

It's hard to be technical / clear / specific to every last detail, I'm doing my best. Maybe I'm wording it wrong or I forgot to mention something, I dunno.

 

[No_OBsT33R]

Moved....

 

[chuyler1]

No_OBsT33R,

You are wasting your breath. Everyone here, as far as I can tell, understands what an open and closed diff is. You are now stating the obvious as if we don't know. All that information is irrelevant to what you have been arguing about except this part...

Int low is a loose free turning car (potential oversteer)
Int high is a tight harder to turn car (potential understeer)

Correct

Accel high is potential roasting of the inside tire, combats throttle oversteer (potential understeer)

Not completely correct. High will create understeer, but when you over throttle, it is the outside tire that will break traction first. This is where your "outside wheel is spinning faster" comment is actually true. The inside tire is pushing the car into understeering and the outside tire will burn up trying to keep pace with it.

Accel low reduces acceleration force (potential oversteer)

Correct.


One thing to be clear about though, if either drive tire turns red on a RWD car, oversteer will occur regardless of the LSD settings. Letting the tires turn red is not the fastest way around a track.

I look at it like this...

Initial: when do you want the LSD to kick in?
Low: Only at full throttle in low gears, Only under hard braking
High: Whenever you touch the throttle, whenever you brake

Accel: Once activated during acceleration, how much power do you want to transfer from the wheel that slips to the wheel that grips?
Low: Very little transfer, good for tracks with tight turns but may cause inside wheelspin when too much throttle is applied
High: Lots of transfer, almost like a welded diff, good for tracks with very few tight turns or cars that have major oversteer issues. Will cause understeer followed by outside wheelspin if too much throttle is applied.

Decel: Once activated during deceleration, how much power do you want to transfer from the wheel that slips to the wheel that grips?
Low: allow both wheels to essentially brake freely. Ovesteer will likely occur if you don't brake in a straight line.
High: forces both wheels to maintain the same rotational speed under braking. Induces understeer under heavy braking which can be safer on fast tracks like LeSarthe.

 

[No_OBsT33R]

The in game adjusters reflect the percentage of power retained, then transferred. 100% = the 50% on either side. So 100% = diff lock & 0 = open diff. The closest we can get to a locked diff is 60%. the closest to open is 5%.

With our 25/25 example on an open diff.

Our example car has 500ft-lb of torque. It's taking a turn that the inside wheel is resisting causing the diff to slip, the car will ONLY put down as much power as the inside wheel needs to go forward.

Our example is 25%. Because the diff splits power equally until it has resistance, each side has 50% of 500. That gives us 250/250. If the inside wheel can only use 25% of it's 250, that gives us 62.5th-lb.

With an open diff this would give us 62.5/62.5, meaning we are using 62.5th-lb on the inside tire and 62.5th-lb on the outside tire.

With a locked diff we would put down 250/250 even though the inside tire only needs 62.5th-lb it overpowers it with the extra 187.5th-lb of torque & the tire roast.

A car with a LSD accel setting of 5 would put down 71.876/71.876 while a accel setting of 60 would put down 175/175.

You want to give the inside tire more power then the minimum required without passing the tires threshold of grip.

ONCE you break traction on the outside with an LSD the inside will keep retaining the power it needs (the outside wheel was following a longer path and already spinning faster) on the inside to move forward.

When you break traction on an open diff (break out the outside) the difference in resistance becomes 100% and power being put down making it to the ground becomes 0/0 the spinning wheel eats up the power not allowing any to go to the ground, you don't move.

A locked diff in a turn is already slipping the inside wheel, if the outside goes it's a tail slide.

With a LSD it will retain the percentage you choose over the minimum required, so long as it has grip, and doesn't overpower it. An accel setting of 5 will keep (500/2)*5% = 12.5ft-lb + (our example 62.5) = 75ft-lb for the wheel on the inside tire. When a accel setting of 60 will keep 150ft-lb + 62.5 = 212.5 so long as it hasn't overpowered it's turn radius and broke out along with the other side.

The outside breaks out because the power put down over powers the tires grip ability. The more weight the more grip the tire has and therefore more power it can handle before breaking out. However a heavier outside helping the outside grip usually lightens the inside making the inside tires have less grip and therefore easier to overpower the grip level of the tires.

 

[Motor City Hami]

No_OBsT33R it is time for you to put up or shut up. All of these long resposes insisting that you have it figured out and that everyones is just too stupid to see the light. You go on and on and on describing the LSD trying to relate it to a real world diff (by the way I can come up with 9 different styles of real world diffs).

Like I said in the OP, does this community have the ability to cut through all of the thoeries and B.S. and just say what the LSD does in GT5. Move the lever up, what does it do? Move it down, what is the result. We can melt down your thoery to this:

Int low is a loose free turning car (potential oversteer)
Int high is a tight harder to turn car (potential understeer)
Accel high is potential roasting of the inside tire, combats throttle oversteer (potential understeer)
Accel low reduces acceleration force (potential oversteer)

I think many of us (as well as the in-game notes) will disagree with your description of Accel.

Put up or shut up. Post a car with your suspension and LSD settings and let the community have a try at improving it. We will change nothing but LSD settings and see where we net out.

 

[dr_slump]

Post a car with your suspension and LSD settings and let the community have a try at improving it. We will change nothing but LSD settings and see where we net out.

He's the owner of a tuning garage. There are several tunes.

 

[No_OBsT33R]

The in game adjusters reflect the percentage of power retained, then transferred.

Each side gets 50%

50%left / 50%right

100% = the 50% on either side

1 click of the slider = 1% of the 50%

So 100% = diff lock

0 = open diff.

The closest we can get to a locked diff is 60%. (setting 60)

The closest to open is 5%. (setting 5)

Read my last post for more details, I updated and cleaned it up.

60/60/60 is not a locked diff, just as close as you can get in the game, while 5/5/5 is not an open diff, just as close as the adjustable LSD can get in the game (the game does have open diffs) those are usually on the cars that handle much differently after installing an Adj LSD and the default diffs greyed out settings are mirrored.


If you want to improve a tune of mine grab my Yellowbird . But improving a tune only reflects more time testing/adjusting. You can do a lot with great feel for the game and ample time to make adjustments until it feels good. You don't need to know anything except that X feels better then Y.

 

[Motor City Hami]

He's the owner of a tuning garage. There are several tunes.

Several tunes? I found one and a couple that he's working on.

 

[dr_slump]

Several tunes? I found one and a couple that he's working on.

Oh, I see....
Only 2 tunes:
LFA and the Yellowbird

 

[No_OBsT33R]

Several tunes? I found one and a couple that he's working on.

It's quality, not quantity

Go for the YB

or pick a car any car (so long as I got it)

60/60/60 is not a locked diff, just as close as you can get in the game, while 5/5/5 is not an open diff, just as close as the adjustable LSD can get in the game (the game does have open diffs) those are usually on the cars that handle much differently after installing an Adj LSD and the default diffs greyed out settings are mirrored.


If you want to improve a tune of mine grab my Yellowbird . But improving a tune only reflects more time testing/adjusting. You can do a lot with great feel for the game and ample time to make adjustments until it feels good. You don't need to know anything except that X feels better then Y.

 

[Motor City Hami]

Oh, I see....
Only 2 tunes:
LFA and the Yellowbird

He's being pretty bold for a guy who only has two tunes posted. Just continues to add to his credibility.

 

[No_OBsT33R]

He's being pretty bold for a guy who only has two tunes posted. Just continues to add to his credibility.

Quality not quantity

Go for the YB...... Join the club already doing so... For a while now...

 

[chuyler1]

When you break traction on an open diff (break out the outside) the difference in resistance becomes 100%

No no no. Open diff = inside wheel spin exiting a turn. Try it out before you post another thing.

The outside rear tire will have significantly more weight on it exiting a turn. With an open diff, the inside tire will break traction first because it has less weight on it, the tire is being compressed less, and it is the path of least resistance. Once it breaks loose, 100% of all available torque would be released in the form of wheelspin giving 0 torque to the outside tire. Unless a slip limiter kicks in, the outside tire will never spin. Since GT5 doesn't actually have an open diff, typical situations show that shortly after one tires spins if the throttle is not modulated, the outside tire will also spin as some torque is transferred from the inside wheel to the outside wheel.

All your theories of how the LSD works are pretty sound...but you can't seem to get past this FACT. Low settings allow inside wheel spin while high settings prevent it and occasionally replace it with outside wheelspin. Controlling wheelspin is just as important as controlling oversteer/understeer...especially since the oversteer could be caused by LSD settings that are too high or too low.

 

[No_OBsT33R]

No no no. Open diff = inside wheel spin exiting a turn. Try it out before you post another thing.

The outside rear tire will have significantly more weight on it exiting a turn. With an open diff, the inside tire will break traction first because it has less weight on it, the tire is being compressed less, and it is the path of least resistance. Once it breaks loose, 100% of all available torque would be released in the form of wheelspin giving 0 torque to the outside tire. Unless a slip limiter kicks in, the outside tire will never spin. Since GT5 doesn't actually have an open diff, typical situations show that shortly after one tires spins if the throttle is not modulated, the outside tire will also spin as some torque is transferred from the inside wheel to the outside wheel.

All your theories of how the LSD works are pretty sound...but you can't seem to get past this FACT. Low settings allow inside wheel spin while high settings prevent it and occasionally replace it with outside wheelspin. Controlling wheelspin is just as important as controlling oversteer/understeer...especially since the oversteer could be caused by LSD settings that are too high or too low.

I said the outside wheel (it don't matter, it's the same for the inside) i never gave the reason it broke loose simply what happens if it does. If either wheel breaks out in an open diff its the same power moving the car forward becomes 0. I already explained all this, and that I don't disagree the weight plays a role, it's just the role it plays the LSD doesn't see until the end result (slippage) the LSD doesn't care if the wheel slips because it hits a patch of leaves, ice, or overpowers it's tires on the pavement on either side. Open diff any wheel slips power moving the car forward goes to 0. I simply said outside wheel, the same for the inside. I also went into the detailing of weights role.

The power / weight balance is complicated and is managed through the suspension tuning. We drop the height to lower the amount of weight transfer, then adjust the suspension to resist more or less the rate the weight is rotated around the center of gravity & amount of dip/dive/lean.

The LSD is there to manage the power delivered while the suspension is managing the weight (as best it can) the LSD sees the result weight transfer has on the tires only when they exceed their ability, not the weight transfer itself.

 

[chuyler1]

I know the LSD doesn't care about weight transfer, I know it doesn't care which wheel slips.

What I am getting at is that knowing what wheel slips first is a clue as to how to tweak the LSD.

If you keep having issues with the inside tire breaking loose and the outside tire is fine, you most likely need to increase the LSD settings.

If you are having issues with the outside tire breaking loose while the inside tire is fine, the LSD settings are likely too high.

If you break loose both tires, the only thing that is going to help you is proper throttle modulation and/or traction control.

 

[No_OBsT33R]

All your theories of how the LSD works are pretty sound...but you can't seem to get past this FACT. Low settings allow inside wheel spin while high settings prevent it and occasionally replace it with outside wheelspin.

I don't disagree with that., I think it's oversimplified and a little more complicated, but that does sum it up.

 

[No_OBsT33R]

I know the LSD doesn't care about weight transfer, I know it doesn't care which wheel slips.

What I am getting at is that knowing what wheel slips first is a clue as to how to tweak the LSD.

Agreed!

If you keep having issues with the inside tire breaking loose and the outside tire is fine, you most likely need to increase the LSD settings.

Yeah, to me it seems like the accel setting is too high, the inside wheel is retaining more power then the tire can handle.

If you are having issues with the outside tire breaking loose while the inside tire is fine, the LSD settings are likely too high.

That's a tough one possibly too high of an accel setting coupled with too low of an INT setting, so I'd say a little of both.

If you break loose both tires, the only thing that is going to help you is proper throttle modulation and/or traction control.

Yeah, agreed.

 

[No_OBsT33R]

Chuyler, agree or disagree on the following?

The in game adjusters reflect the percentage of power retained, then transferred (Both sides always have an = amount.)

Each side gets 50%

50%left / 50%right

100% = the 50% on either side

1 click of the slider = 1% of the 50%

In a Turn (as going straight it's always 50/50 until slip)

So 100% = diff lock

0 = open diff.

The closest we can get to a locked diff is 60%. (setting 60)

The closest to open is 5%. (setting 5)

Read my last post for more details, I updated and cleaned it up.

60/60/60 is not a locked diff, just as close as you can get in the game, while 5/5/5 is not an open diff, just as close as the adjustable LSD can get in the game (the game does have open diffs) those are usually on the cars that handle much differently after installing an Adj LSD and the default diffs greyed out settings are mirrored.

Improving a tune only reflects more time testing/adjusting. You can do a lot with great feel for the game and ample time to make adjustments until it feels good. You don't need to know anything except that X feels better then Y.

 

[Basilea]

All I know for sure is a low setting of 5/5/5 gives me inside wheel spin. The inside wheel turns red on the indicator. And I can get rid of it with higher accel and or initial.

 

[Rotary Junkie]

Well actually chuyler, there IS an open diff simulated in GT5 in a few cases... Generally older vehicles (Challenger, GT350 come to mind). Those vehicles will spin the inside tire down the next straight if you let them.

Edit: That's what I get for not refreshing.

Now then, as for open diffs losing all forward traction when one tire "breaks loose"... Not quite. An open diff will apply however much power it takes to spin either tire to the other... So if one tire is on ice and the other is on dry pavement, yes, you lose all forward thrust. If one is simply spinning due to traction loss there will still be forward acceleration, but only as much as it takes to keep the spinning tire spinning.

 

[chuyler1]

That's a tough one possibly too high of an accel setting coupled with too low of an INT setting, so I'd say a little of both

Low int with high accel would definitely cause "snap" oversteer. Something like 5/60/xx. Before the inside wheel ever breaks free, power would be instantly transferred to the outside wheel. The abrupt change would cause the outside tire to break free, followed shortly by the inside tire. However outside wheelspin could happen any time accel is too high for a given radius turn.

 

[chuyler1]

Chuyler, agree or disagree on the following?

For the most part yes. I'm not sure it can be assumed that that each click is a percentage, but its definitely relative.

 

[chuyler1]

Well actually chuyler, there IS an open diff simulated in GT5 in a few cases... Generally older vehicles (Challenger, GT350 come to mind). Those vehicles will spin the inside tire down the next straight if you let them.

Now then, as for open diffs losing all forward traction when one tire "breaks loose"... Not quite. An open diff will apply however much power it takes to spin either tire to the other... So if one tire is on ice and the other is on dry pavement, yes, you lose all forward thrust. If one is simply spinning due to traction loss there will still be forward acceleration, but only as much as it takes to keep the spinning tire spinning.

Your correct with both. I was referring mainly to the actual LSD. You can't get the custom LSD to run open. Do you know what the Challenger/GT350 has for default settings?