Are you using too much camber (>1.5)? real RUF has bigger rear camber too

[Mt. Lynx]

Yes, that is the sign of excessive camber.
That is also the reason why I don't use camber these days, if you drive smoothly, your outside tire will gain more traction from camber. But if you drive rough (using digital controller), the outside tire will loose traction if you correct the steering in the middle of the corner. To compensate zero camber I use harder spring rate and lower ride height.

Sounds right, but this style of tuning will also require a certain driving style, wich would not suit me at all (if that style suits you, you should be quick with the Mercedes SLR). I like my cars to have rather soft suspension, and I may overdo the camber just little bit, to be able to brake deeper into a turn. I brake almost to apex, and get harder on the throttle just when I leave apex, thus having a bit of oversteer is beneficial for me.

BTW, if you are interested (and still have GT2) why don't you all join setup vs setup thread? we are currently trying to tune cobra coupe in rome night. You can comment on my tuning on jaguar xjr too (no camber).

Would be nice, but I don´t own GT2, sadly.

 

[Leonidae]

there's one thing: I just can't stand RR's.. any of them. and they hate me.

 

[Uncle Harry]

I tune with regard to feel of the car, I do not look at replays to see body movement and wheel angles.
In GT4 I generally use more front camber than rear. A couple of exceptions are some light Mid engine cars that seem to work better with more rear camber.
In GT4 you can no longer use 1 set of settings accross the board that seemed to work for GT3. Each car / track / suspension / tire combo needs to be looked at.

 

[Scaff]

I tune with regard to feel of the car, I do not look at replays to see body movement and wheel angles.
In GT4 I generally use more front camber than rear. A couple of exceptions are some light Mid engine cars that seem to work better with more rear camber.
In GT4 you can no longer use 1 set of settings accross the board that seemed to work for GT3. Each car / track / suspension / tire combo needs to be looked at.

Agree 100% with you on that, each combo needs to be looked at and tuned seperatly in my opinion.

You may want to have a look at my tuning guide as its writen with just such an approach in mind (link in my sig).


@sucahyo
You keep suggesting that zero camber should be used, but this would only be a wise thing to do if no roll at all was occuring. As this is never going to be the case (unless you change the suspension for some iron rods), you are always going to get some movement that is going to deflect the tyre and as such require some camber to compensate.

I can understand your position on minimal camber settings (but don't agree that it will work for everyone), but I can't see the logic in a zero setting?

Regards

Scaff

 

[Mt. Lynx]

Agree with Scaff here. Zero camber is actually not used IRL, even for roadcars, as they always have some toe and camber, mainly for appropriate balance in day-to-day use. In racecars, these are exaggarated to the point where you can actually feel how they work. Well, if you could change it on your average car you could maybe feel some difference, but probably very little.
I have to point out that I don´t know if all roadcars use this, but most haveit, and they are most likely not very similar from car to car.

 

[sucahyo]

@sucahyo
You keep suggesting that zero camber should be used, but this would only be a wise thing to do if no roll at all was occuring. As this is never going to be the case (unless you change the suspension for some iron rods), you are always going to get some movement that is going to deflect the tyre and as such require some camber to compensate.

I can understand your position on minimal camber settings (but don't agree that it will work for everyone), but I can't see the logic in a zero setting?

No, you get me wrong, I am not suggesting anyone to use zero camber, because to use zero camber you must use rock hard suspension and very low ride height, which is not everyone preference. What I am suggesting is comparing you current camber with zero camber (or almost zero, increase front or rear a little to match current handling). See if your car get thrown sideways in highspeed corner more or less. See if your car have grip in slow corner more or less. Use the feeling you get to decide to increase or decrease current camber. Because the understeer and oversteer feeling can be have from both using small or big camber.
To prevent big powered car from spin in corner, using camber also really help. Using big front camber will surely reduce car spinning on acceleration. But also increase understeer on corner, that is why I usually compensate by adding some rear camber to make the car more oversteer.

My reason to use zero camber:

• I use hard spring rate in GT2. In GT2, on most car, the optimum spring grip is above 12.0, and sometime 20.0. In GT4 I find using 4.0 and 12.0 have the exact same 1000m time, but using 20.0 give slower time. In GT4 I will not use zero camber.
• I feel using zero camber have more lateral grip (less thrown outside) than 1.0 or 2.0 camber on my tuning. But this only work on car with bellow 2 degree body roll stock on my test. I thinking to use 1.0 degree camber on my next shelby cobra coupe setting on 20.0/20.0 spring rate. On this rock hard suspension using 2.0 feel more understeer than 0.0.

In GT4 I will use photomode as final measurement wether my camber is correct or not, not as initial setting.
For this car (from Greycap's gallery).

I will use 1.8 front camber for left car, and 5.2 front camber for right car (assuming this is the most important corner in track). Because the left car (greycap's) has 1.8 front roll, and the right car (opponent, stock?) has 5.2 front roll.

can you explain about tire deflect? I don't see it in any GT4 picture I have

 

[Mt. Lynx]

can you explain about tire deflect? I don't see it in any GT4 picture I have

I don´t think it is shown visually in GT4, but that it is simulated through behavior of the car. I´m not sure about this, since GT4 physics never allow you to let one tyre leave the ground due to centrifugal forces or gravity. GT4 do not allow you to set tyrepressure either, wich would add another dimension to grip tuning and corner settings.
Heat is simulated, so there has to be some deflect simulation too, or else the heatsignature of the grip would come out askew.
I´m not really sure about this, so maybe we should wait for the experts opinion. Scaff?

 

[Greycap]

Because the left car (greycap's) has 1.8 front roll, and the right car (opponent, stock?) has 5.2 front roll.

That shows that my camber tuning seems to be quite spot on, the car actually had 2.0 front camber!

No idea about the camber angle of the opponent, but it's a stock one and one thing is for sure: stock muscle cars sway more than boats in a heavy swell.

And thanks for using my shot as a reference!

 

[Scaff]

In real life when a car is cornering the suspension system travels in an arc (rather than straight up and down) which means that the tyre will very rarely remain perpendicular with the road as the suspension moves. As such as a car turns, the severity of the corner, aggressiveness of the driver’s style and the cars suspension set-up will mean that the relationship of the tyre to road will rarely be the same for every corner. Additionally road car suspension itself contains a degree of ‘slack’, coming from the use of rubber suspension bushes (these are needed so the car is not incredibly uncomfortable).

All of the above will cause a degree of ‘offset’ between the tyre and road surface.

Tyre deflection is caused by the obvious fact that a tyre is not a solid object, and as such when forces (particularly lateral forces during cornering) are placed on it, then it deforms, which changes the size and shape of the contact patch. As can be seen in the picture below.

All the above factors are the reason why in real life, almost all cars will require a degree of negative camber to help ensure that the tyre retains good contact with the road during cornering.

The following is an excellent explination of the pros and cons of camber settings from Tyre Tech

The camber angle identifies how far the tire slants away from vertical when viewed directly from the front or back of the vehicle. Camber is expressed in degrees, and is said to be negative when the top of the tire tilts inward toward the center of the vehicle and positive when the top leans away from the center of the vehicle.

Since street suspensions cannot completely compensate for the outer tire tipping towards the outside when the vehicle leans in a corner, there isn't a magical camber setting that will allow the tires to remain vertical when traveling straight down the road (for more even wear), and remain perpendicular to the road during hard cornering (for more generous grip).

Different driving styles can also influence the desired camber angle as well. An enthusiastic driver who corners faster than a reserved driver will receive more cornering grip and longer tire life from a tire aligned with more negative camber. However with the aggressive negative camber, a reserved driver's lower cornering speeds would cause the inside edges of the tires to wear faster than the outside edges.
What's the downside to negative camber? Negative camber leans both tires on the axle towards the center of the vehicle. Each tire develops an equal and offsetting "camber thrust" force (the same principle that causes a motorcycle to turn when it leans) even when the vehicle is driven straight ahead. If the vehicle encounters a bump that only causes one tire to lose some of its grip, the other tire's negative camber will push the vehicle in the direction of the tire that lost grip. The vehicle may feel more "nervous" and become more susceptible to tramlining. Excessive camber will also reduce the available straight-line grip required for rapid acceleration and hard stops.

Appropriate camber settings that take into account the vehicle and driver's aggressiveness will help balance treadwear with cornering performance. For street-driven vehicles, this means that tire wear and handling requirements must be balanced according to the driver's needs. The goal is to use enough negative camber to provide good cornering performance while not requiring the tire to put too much of its load on the inner edge while traveling in a straight line. Less negative camber (until the tire is perpendicular to the road at zero camber) typically will reduce the cornering ability, but results in more even wear.

Even though they have some of the most refined suspensions in the world, the next time you see a head-on photo of a Formula 1 car or CART Champ Car set up for a road course, notice how much negative camber is dialed into the front wheels. While this is certainly an example of wear not being as important as grip, negative camber even helps these sophisticated racing cars corner better.

Now in regard to how GT4 deals with this is open to discussion, certainly I have never visiably seen this displayed, but I do believe that GT4 accounts for this (even if its just preset values).

Zero camber would only be of benefit if no change in the tyres relationship to the road surface occurred during cornering, so even if GT4 does just use preset values to represent this, I would argue that zero camber values would very rarely be of use.

However as I have always maintained, the ‘correct’ value is what works for the driver and his/her car.

Regards

Scaff

 

[Dave_George]

Interesting thread...

We have just finished 17 weeks of the Nurburgring race series over in the long race section and each week not only was my camber setting different for each car, but it changed with regards to the suspension settings i was using.

The final weeks Ruf Yellowbird seemed to work for me with more rear camber than front, and the Toyota MR2 we drove i found needed very little camber.

My conclusion is that there is no easy answer or formula, only by adjusting in small steps and testing will you find what works for you and any given car/track combination.

regards

David

 

[sucahyo]

there's one thing: I just can't stand RR's.. any of them. and they hate me.

Play around with them using extreme tuning, try to make it handle worse, like using 6.0/6.0 camber . Then after you satisfy, tune to make it handle better .

I tune with regard to feel of the car, I do not look at replays to see body movement and wheel angles.

I see, many people prefer to do that too. For me, tuning by visual is also neccessary. As I drive from rear view, I can easily see which part of the car is wobbling, bumping, or swaying, sometime I can see rolling too. If only the car rear or front is jiggling I use 1/10 or 10/1 damper, etc.

In GT4 you can no longer use 1 set of settings accross the board that seemed to work for GT3. Each car / track / suspension / tire combo needs to be looked at.

What 1 set of setting do you refer to?

That shows that my camber tuning seems to be quite spot on, the car actually had 2.0 front camber!

Interesting .

No idea about the camber angle of the opponent, but it's a stock one and one thing is for sure: stock muscle cars sway more than boats in a heavy swell.
And thanks for using my shot as a reference!

I like it .

I´m not sure about this, since GT4 physics never allow you to let one tyre leave the ground due to centrifugal forces or gravity.

I 100% believe GT4 physics allow us to lift one wheel, but this is only possible with hacked value (even the hacked value must still follow the GT4 physics rule). I still don't have the chance to test this though.

Heat is simulated, so there has to be some deflect simulation too, or else the heatsignature of the grip would come out askew.

I choose the askew one .

Tyre deflection is caused by the obvious fact that a tyre is not a solid object, and as such when forces (particularly lateral forces during cornering) are placed on it, then it deforms, which changes the size and shape of the contact patch. As can be seen in the picture below.

I see.

All the above factors are the reason why in real life, almost all cars will require a degree of negative camber to help ensure that the tyre retains good contact with the road during cornering.

Yes, same. On real life there is sophisticated suspension that don't need statis camber isn't it? (nissan serena?) I am sure this is banned in F1.

The following is an excellent explination of the pros and cons of camber settings from Tyre Tech

Notice that different cornering speed result in different body roll amount.

Since street suspensions cannot completely compensate for the outer tire tipping towards the outside when the vehicle leans in a corner, there isn't a magical camber setting that will allow the tires to remain vertical when traveling straight down the road (for more even wear), and remain perpendicular to the road during hard cornering (for more generous grip).

I translate "remain perpendicular to the road during hard cornering" as camber having the same angle as body roll, am I wrong?

Now in regard to how GT4 deals with this is open to discussion, certainly I have never visiably seen this displayed, but I do believe that GT4 accounts for this (even if its just preset values).

As I believe all that simulated is also displayed, I believe tire deflect not implemented in GT engine. The tire will not deform in any way in GT engine.

Zero camber would only be of benefit if no change in the tyres relationship to the road surface occurred during cornering, so even if GT4 does just use preset values to represent this, I would argue that zero camber values would very rarely be of use.
However as I have always maintained, the ‘correct’ value is what works for the driver and his/her car.

Me too. But I still think photomode is important tool to judge the camber value used. Different tuning or driving habits can result in different car roll, this roll can be used to decide the required camber value.

The final weeks Ruf Yellowbird seemed to work for me with more rear camber than front, and the Toyota MR2 we drove i found needed very little camber.

Interesting .

My conclusion is that there is no easy answer or formula, only by adjusting in small steps and testing will you find what works for you and any given car/track combination.

I consider seeing how the wheel/car angle in corner in photomode as a way of testing too.


BTW, I found a clue that stock S2000 has -0.5/-1.5 camber.

 

[Scaff]

Yes, same. On real life there is sophisticated suspension that don't need statis camber isn't it? (nissan serena?) I am sure this is banned in F1.

You are refering to active suspension, which does indead do many onthe things you are refering to, an is now banned in F1.

Notice that different cornering speed result in different body roll amount.

Yes, which is what I have been saying for a while, its why one camber setting will never be ideal for every corner on a track, and why I believe that zero camber should be avoided.

I translate "remain perpendicular to the road during hard cornering" as camber having the same angle as body roll, am I wrong?

Its more that the tyre will be at a 90degree angle to the road to allow he maximum contact patch to remain in contact with the road. As suspension travels in an 'arc', which does not exacatly follow the roll of a car the two are rarely the same.

Body roll is an indicator (as you have correctly suggested) but it is not the 'holy grail' of camber setting.

Me too. But I still think photomode is important tool to judge the camber value used. Different tuning or driving habits can result in different car roll, this roll can be used to decide the required camber value.

See my last point

I consider seeing how the wheel/car angle in corner in photomode as a way of testing too.

Would not disagree visual information is an important part o fthe tuning process, however I still believe that 'feel' is more important.

BTW, I found a clue that stock S2000 has -0.5/-1.5 camber.

Yes but as he same piece goes on to explain, the S2000 has a very particular issue with the rear end being very 'snappy', something that the Honda engineers have tried to address with these setting, but not 100% done.

Its not a great example of 'standard' settings, but is a good example of how camber can be used (in conjunction with toe in this example) to try and fix what is generally considered to be a chassis issue.

Regards

Scaff

 

[sucahyo]

Yes, which is what I have been saying for a while, its why one camber setting will never be ideal for every corner on a track, and why I believe that zero camber should be avoided.

Ok. So, you think 0.5 angle is better than none (if the car roll is very small)?

Its more that the tyre will be at a 90degree angle to the road to allow he maximum contact patch to remain in contact with the road. As suspension travels in an 'arc', which does not exacatly follow the roll of a car the two are rarely the same.

Yes, but we don't know for sure how GT physics implement that. If it does it still possible to measure that, although a bit harder, we have to measure how bottom part of the tyre angled to the tire angle. And measuring how the tire angled is hard because the tire is usually shown very dark. Measuring how the bottom part of the tire angled to the car body is easier.
After seeing some of both GT2 and GT4 picture with zero zamber, I tend to believe that the tyre angle has always follow the angle of the body.

I think red line angle will always be 90 degree added with camber angle, and blue line angle will depend on car/suspension/driver/corner/tire/downforce/etc. If what you said is true, then the tire relative angle to the body would be different when cornering or when stopping. So far I don't see that.

Body roll is an indicator (as you have correctly suggested) but it is not the 'holy grail' of camber setting.

Yes, it is just a tool to help.

Would not disagree visual information is an important part o fthe tuning process, however I still believe that 'feel' is more important.

Ok.

Yes but as he same piece goes on to explain, the S2000 has a very particular issue with the rear end being very 'snappy', something that the Honda engineers have tried to address with these setting, but not 100% done.

Yes, the driver even mention going to add some more negative rear camber to that car ....... Maybe like this is better (spoon)?

 

[nos2]

I usually just tune the car based on feel. I ususally end up with front cambers at 2.5-3.2 degrees (a little bit less on race cars). I don't think the GT4's photomode is accurate enough where you can use it to mearsure the body roll. There are some aspects of real physics that GT4 doesn't simulate. Like I slam most of my cars to the lowest ride height, with moderately soft suspension. IRL this would be undrivable, but yest in GT4 it works fine. The only way we can use camber like real life is if we know the tire's temperature reading on specific area.

 

[sucahyo]

I usually just tune the car based on feel. I ususally end up with front cambers at 2.5-3.2 degrees (a little bit less on race cars).

The downside of using feeling is you can only feel the oversteer and understeer reaction of the car mostly. You rarely able to tell the sideway reaction of the car because it's so subtle (if you don't compare it with lower camber). Feeling the acceleration or braking difference in straight line is hard too. If you don't use visual check, at least compare it with both lower or both higher camber with the same neutrality.
example: If your current camber is 2.5/1.5, try comparing it with 1.5/1.0 and 3.5/2.0, and see if 1.5/2.5 really make your car handling worse. Don't tune with just small increment, try big increment too and then use the aproximately correct one.

I don't think the GT4's photomode is accurate enough where you can use it to mearsure the body roll.

I think it's accurate enough. If it doesn't then I already hate it by now. Do you have some complain about inconsistent feel vs visual?
If I can show that in GT2 some RUF have bigger real roll (sign of heavier rear), where in real life RUF YB use bigger rear chamber, then I say GT4 is accurate enough to show that too.
Roll in GT give hint of weight distribution correctly, even if the amount maybe off. But I prefer using camber value based on this "maybe off" roll than using real life reference, because this is what physics engine simulated and accepted.

There are some aspects of real physics that GT4 doesn't simulate. Like I slam most of my cars to the lowest ride height, with moderately soft suspension. IRL this would be undrivable, but yest in GT4 it works fine.

What do you mean by undrivable IRL? Isn't stock car usually have around 2.0-4.0 spring rate in GT4? And isn't it impossible for us to use spring lower than 2.0 (4.0?)?
If what you said is true, I think this is a sign of incorrect feel feedback, not visual.

The only way we can use camber like real life is if we know the tire's temperature reading on specific area.

Yes, but I don't think I want GT to become more like nascar series, too much tuning .


You can use photomode cornering observation to:

• know that you use correct camber for spesific corner that you consider important. If no corner is important we can still find the average camber needed in every corner.
• find maximum roll on hardest corner in the track. With this we can decide what maximum camber that we should need. Wether our current camber is too much or not, etc. Since camber being too small is better than too big because smaller camber help straight line traction, knowing maximum roll can help us tune better.

 

[Scaff]

The downside of using feeling is you can only feel the oversteer and understeer reaction of the car mostly. You rarely able to tell the sideway reaction of the car because it's so subtle (if you don't compare it with lower camber). Feeling the acceleration or braking difference in straight line is hard too. If you don't use visual check, at least compare it with both lower or both higher camber with the same neutrality.
example: If your current camber is 2.5/1.5, try comparing it with 1.5/1.0 and 3.5/2.0, and see if 1.5/2.5 really make your car handling worse. Don't tune with just small increment, try big increment too and then use the aproximately correct one.

This may be down to different tuning methods, but I could not disagree more with this. While the visual aspect of tuning is important, as is the use of data, I still find 'feel' to be the single most important factor when tuning.

One thing that may bias this is my use of the DFP, which give a great level of feel. Are you still running GT4 on a PC and useing the keyboard? as that may explain a lot.

I think it's accurate enough. If it doesn't then I already hate it by now. Do you have some complain about inconsistent feel vs visual?
If I can show that in GT2 some RUF have bigger real roll (sign of heavier rear), where in real life RUF YB use bigger rear chamber, then I say GT4 is accurate enough to show that too.
Roll in GT give hint of weight distribution correctly, even if the amount maybe off. But I prefer using camber value based on this "maybe off" roll than using real life reference, because this is what physics engine simulated and accepted.

Again I would have to disagree in part with this, GT4's photomode was designed as just that, the ability to grab photos from the game. We have no way of knowing 100% that every element of the physics engine is then visualy represented in photomode shots.

And even using photoshop, the measurement of angles in this way will always involve a margin of error. As we are dealing with very small angles here, I would never say that the results are 100% correct.

Yes, but I don't think I want GT to become more like nascar series, too much tuning .

I'm quite the opposite, I'm frequently frustrated by the lack of tuning detail in GT4 and would be quite happy with much more detailed tuning options. One of the reasons I love Richard Burns Rally is that it allows full tuning of damper settings and total differential mapping.

You can use photomode cornering observation to:

• know that you use correct camber for spesific corner that you consider important. If no corner is important we can still find the average camber needed in every corner.
• find maximum roll on hardest corner in the track. With this we can decide what maximum camber that we should need. Wether our current camber is too much or not, etc. Since camber being too small is better than too big because smaller camber help straight line traction, knowing maximum roll can help us tune better.

While I agree that photomode is a useful tool for looking at camber I would dispute that a lower value is always better that a higher value. Very few of the courses in GT4 have long enough straights that would make this true.

Also if you tune just for the straights you may well lose speed out of a corner (due to the lower camber) which will hurt you more on the following straight that you would gain backk from running less negative camber.

The principal factor about straight line performance on a track is how fast you can exit the corner before the straight.

You would have to be running very high negative camber for the opposite to become true, and by that point the level of negative camber you would be running would hurt you both in the corner and the straight.

This again can be clearly seen in Formula 1 cars, which run high levels of negative camber, even on tracks with long straights. This was clearly visable in last weekends Grand Prix.

Regards

Scaff

 

[sucahyo]

What do you disagree? I am not saying visual is more important, read again, I am explaining tuning with feeling.

You don't believe GT4 visual correctness, we have different opinion on this. I love GT4 because its feeling and visual corectness. So using photomode or replay to see how the car roll is ok for me. At least you know that photomode shows camber correctly.

If you can zoom to 2 meter apart from the tyre, I am sure the angle will be accurate to 0.2 degree. Try to measure the angle in previous chevy for your self and see how much error you have.

You are comparing correct camber with too low camber. I am comparing too big with too low. Both will result in less corner grip, but too high is worse because it have less straight grip too.

Is richard burn's rally tuning as complex as nascar?

BTW, is F1 car camber as high as GT500 or JGTC or Touring car camber?

 

[Scaff]

What do you disagree? I am not saying visual is more important, read again, I am explaining tuning with feeling.

Right sorry about that, it read as if you were favoring visual over tuning, which for me would be wrong.

You don't believe GT4 visual correctness, we have different opinion on this. I love GT4 because its feeling and visual corectness. So using photomode or replay to see how the car roll is ok for me. At least you know that photomode shows camber correctly.

If you can zoom to 2 meter apart from the tyre, I am sure the angle will be accurate to 0.2 degree. Try to measure the angle in previous chevy for your self and see how much error you have.

Its more that I will never 100% trust somethin unless I can verify it against physical data. I mean you would not measure a real cars camber from a photo and consider it 100% acurate, you would measure it on the car.

That said, it is a useful indicator, but for me its just that an indicator.

You are comparing correct camber with too low camber. I am comparing too big with too low. Both will result in less corner grip, but too high is worse because it have less straight grip too.

Thats fine, just talking at cross purposes then. 👍

Is richard burn's rally tuning as complex as nascar?

I would say yes its at least as complex as most NASCAR titles, but the focus is on different areas, not surprising givne that NASCAR tuning is based on a very fixed area (oval tracks).

BTW, is F1 car camber as high as GT500 or JGTC or Touring car camber?

That would depend on the car, track and driver. But in most cases yes F1 cars do run some quite high negative camber values.

Regards

Scaff

 

[Uncle Harry]

What 1 set of setting do you refer to?

.

Sucahyo, I found a set of numbers or rules that worked well for all cars.
I forget exactly what they are but as a rule I would set front camber at 4 and rear at 2. I would lower ride hieght 5 clicks and increase spring rate 5 clicks. Things like that.
This does not work in GT4 so each car has to be sorted individually to get best results.

How can looking at pictures of angles etc tell you if the car feels good or bad, improve lap time or decrease lap time. All it does is confirm that PD has the numerical values tied in with the graphics.
Tuning for feel is what matters. If the car is faster than before I know my changes worked. I do not care which way the wheels are pointing visually or how much body roll I have.
Also one has to question the accuracy when measuring of the TV screen.

Love the effort you put in though, some very good stuff you do. I do not think anyone else has looked at GT tuning quite the way you have.👍

 

[sucahyo]

Its more that I will never 100% trust somethin unless I can verify it against physical data. I mean you would not measure a real cars camber from a photo and consider it 100% acurate, you would measure it on the car.
That said, it is a useful indicator, but for me its just that an indicator.

Ok.

That would depend on the car, track and driver. But in most cases yes F1 cars do run some quite high negative camber values.

I see, they seem to use about 4 degree camber front (I measure it range from 3 to 4 in 2005 F1 photos I search). They use small camber for the rear though (<1.5).

This does not work in GT4 so each car has to be sorted individually to get best results.

I see.

How can looking at pictures of angles etc tell you if the car feels good or bad, improve lap time or decrease lap time.
Tuning for feel is what matters. If the car is faster than before I know my changes worked. I do not care which way the wheels are pointing visually or how much body roll I have.

Camber tuning for me is hard. Feeling the difference between 2.0/1.0 and 1.9/0.9 is impossible for me. I can only feel the car going sideways more if I compare 6.0/3.0 vs 2.0/1.0. For oversteer/understeer characteristic it is easier, I can feel the difference between 2.0/1.0 vs 1.0/1.0.
I can't rely on my laptime because my driving suck. The B-Spec also unreliable because changing both camber by 0.5 rarely change lap time.
The correct way to do it in real life is by temperature reading. I notice even profesional racers don't rely on their feel to tune the car camber. In real life tuning with picture can be expensive and more ineffecient compare to temperature reading, so they not use this. But in GT I think using picture is the only way to do it in theoretical way because we don't have detailed temperature reading.
So, tuning with picture help me. It can save me from doing so many laps.

Also one has to question the accuracy when measuring of the TV screen.

Yes, but 1600x1200 picture in GT4 is good enough to get decent accuracy, I can tell the difference between 4 and 3 degree in 640x480 pix res from F1 by measuring it (0.5 degree accuracy).

Love the effort you put in though, some very good stuff you do. I do not think anyone else has looked at GT tuning quite the way you have.👍

Thanks .

 

[Vision GT]

Off topic here or not...*unsure*

Does changing the camber angle in GT3/4 affect the tire wear?

 

[sucahyo]

Off topic here or not...*unsure*

Does changing the camber angle in GT3/4 affect the tire wear?

From
what I read here, camber do not affect tire wear much.

This remind me, there isn't step by step camber tuning mentioned in here. Can anyone post your camber tuning method?

 

[Scaff]

From what I read here, camber do not affect tire wear much.

In GT4 you need to be running quite high camber values before it has a major impact on tyre wear.

This remind me, there isn't step by step camber tuning mentioned in here. Can anyone post your camber tuning method?

Here my section on Camber tuning from my GT4 suspension and brake tuning guide (the full guide can be downloaded by following thye link in my sig below - well worth a look - and part 2 with differential, gear ratio and downforce tuning will be ready soon).

Camber is the angle of the wheel relative to vertical, as viewed from the front or the rear of the car. If the wheel leans in towards the chassis, it has negative camber; if it leans away from the car, it has positive camber.

GT4 only uses negative camber, as positive camber is very rarely used on cars set up for racing or track work, its function being limited to the set-up of production road cars.

The principal purpose of setting camber is to ensure that the maximum area of the tyres contact patch is used during cornering. As a car corners the suspension and movement of the tyre cause the contact patch to change size as the car rolls.

The downside is that with negative camber the contact patch is minimised when the car is not turning which can reduce straight-line traction for the driven wheels and stability. Also setting too extreme a camber value may mean that the full contact patch of the tyre is never used even during hard cornering.

As camber settings will affect the level of grip at the front and back of the car, it can be used to trim under and over steer if required. Personally I would rarely do this as my main aim with camber is simply to maximise traction while cornering. The rest of the suspension settings can be used to help control under and over steer characteristics. This is however a personal choice based upon the tuners driving style and sometimes the demands of a particular car.

Setting camber is something of a black art as it is only possible to estimate the effect and only through testing will the correct setting be discovered.



Settings

Front Camber
Positive Effects
Increases cornering grip for the front tyres up to a point after which grip will reduce.
Reduces understeer.

Negative Effects
Reduces straight-line traction (for FWD/4WD cars) and stability.
Braking distance increases and stability reduced.
Very high settings can reduce initial turn-in.

Rear Camber
Positive Effects
Increases cornering grip for the rear tyres up to a point, after which grip will reduce.
Reduces Oversteer.

Negative Effects
Reduces straight line traction (for RWD/MR/4WD/RR cars) and stability.
High settings can increase oversteer as the contact patch is distorted.
Less warning when the limited is reached.

The correct way to do it in real life is by temperature reading. I notice even profesional racers don't rely on their feel to tune the car camber. In real life tuning with picture can be expensive and more ineffecient compare to temperature reading, so they not use this. But in GT I think using picture is the only way to do it in theoretical way because we don't have detailed temperature reading.

Not 100% correct. Camber settings in real life (in racing circumstances) are done with a mixture of feel and temp reading. Feel is vital in the real world because if the driver in not happy and/or comfortable with the car they are about to drive they will rarely extract the maximum performance from the car.

A good example of this would be if car 'A' offered huge amounts of grip through the tyres (which is something that can be achieved through computer modelling), but gives little feel and feedback to the driver about when the limit is close. Car 'A' would give almost no warning about when the limit was about to be reached, and very few drivers would feel comfortable getting close to the limit and so the limits of the car would rarely be used. You could then have Car 'B' that has lower overal grip, but gives the driver huge amounts of feel and feedback about the cars limits.

Car 'A' is theoreticaly quicker around a corner as it has more grip, yet the vast majority of drivers would not be able to consistently exploit that grip, as the car would not 'talk' to them. As a result in almost all circumstances car 'B' would be real world quicker.

Its what makes the difference between grip and handling, personally I will take handling over grip any day of the week. If you want to experience this in GT4 take the Lotus Elan out for a drive on N2 tyres, it has very little grip (as it runs on skinny little tyres) yet offers loads and loads of feel and feedback in regard to what it is doing.

You are quite right that in the real world tyre temps (taken across the whole face of the tyre) are of vital importance to set-up, but this is not just limited to camber tuning. Other areas of suspension set-up can give temp imbalance across the tyre face, as can a drivers style.

So, tuning with picture help me. It can save me from doing so many laps.

I think this is were we differ in our approaches, while I do use the visuals in tuning, they are an aid. For me I have to put in the lap time to get the set-up working right.

I find that a 'formula' approach, can result in excellent grip, but miss out on a car that feels right on the limit, and for me that causes major problems in getting a good time with the car.

For example, at the moment I am writing the second part of my GT4 tuning guide and I spend 2 hours last night 'fine' tuning the gear ratios, differential settings and downforce of the BMW M3 CSL that I am going to use for the example.


Regards

Scaff

 

[sucahyo]

Here my section on Camber tuning from my GT4 suspension and brake tuning guide.

can you give step by step example of how you do it? do you stop tuning when the car handling is correct?

Not 100% correct. Camber settings in real life (in racing circumstances) are done with a mixture of feel and temp reading. Feel is vital in the real world because if the driver in not happy and/or comfortable with the car they are about to drive they will rarely extract the maximum performance from the car.

Ok.

I find that a 'formula' approach, can result in excellent grip, but miss out on a car that feels right on the limit, and for me that causes major problems in getting a good time with the car.

Ok, I still using feel too.

For example, at the moment I am writing the second part of my GT4 tuning guide and I spend 2 hours last night 'fine' tuning the gear ratios, differential settings and downforce of the BMW M3 CSL that I am going to use for the example.

Now this is interesting, I also use tool when tuning my gear (excel calc), I can't wait to see how you do it . And check the difference between low and high final drive if you have time. All I know is lower give more spin (in GT4 and GT2), I suspect it make faster acceleration too (it is in GT2).

 

[Scaff]

can you give step by step example of how you do it? do you stop tuning when the car handling is correct?

I would normally drive the car with the default camber setting and see how it feels and what the limit (in cornereing speed) is on the most important corners for the circuit. From that point I would then try the car with camber at +0.5 and - 0.5 front and rear, and test drive each. I would continue this process until I reach a camber value that both 'feels' right and offers the best balance of cornering speeds for the circuits important corners.

Of course if the settings started to cause problems in other areas, such as braking and acceleration I would look at the nature of the circuit to see if this needed to be resolved.

As a base guide I do use the amount of body roll the car experiences, but I only use it as a guide not a limiting factor.

It may sound quite long winded, but it does work for me and I find the process very enjoyable. It the basic theory behind all my tuning.

I also use the positive and negative points I list by area in my guide to use camber to resolve any tuning issues. However as I mention in the guide (and above) I personally rarely use Camber as a method of managing under or oversteer.

Now this is interesting, I also use tool when tuning my gear (excel calc), I can't wait to see how you do it . And check the difference between low and high final drive if you have time. All I know is lower give more spin (in GT4 and GT2), I suspect it make faster acceleration too (it is in GT2).

The gearing section should be an interesting one, I also have an excell calculator I use for looking at gear ratios and there effects, I have attached it below.

Regards

Scaff

 

[sucahyo]

I would normally drive the car with the default camber setting and see how it feels and what the limit (in cornereing speed) is on the most important corners for the circuit. From that point I would then try the car with camber at +0.5 and - 0.5 front and rear, and test drive each. I would continue this process until I reach a camber value that both 'feels' right and offers the best balance of cornering speeds for the circuits important corners.

Such a small increment, I don't think I can do that. See bellow.

It may sound quite long winded, but it does work for me and I find the process very enjoyable. It the basic theory behind all my tuning.

Actually, my camber tuning (based on feel) is a lot longer:
- Use zero camber, drive the car.
- Tune front camber first, use a step higher camber, like 1.0/0.0, and drive the car, compare.
- Use double of previous value, like 2.0/0.0, and drive the car, compare.
- repeat until you feel loss of traction.
- Use zero camber again, drive the car and compare.
- lower or raise the value until you find camber that have the same feeling as zero camber (drive the zero camber again)
- use the half of the final value as your final front camber.
- do the same thing for rear camber. But you can add more or less to neutralize handling
- adjust the other suspension to match current handling
- repeat the procedure from step 1
- try both direction when you feel the car unneutral, ex. if the car understeer try both increasing and decreasing front camber and also increasing and decreasing rear camber.
- if you are not sure try double value
- always compare to zero camber and reverse value to see if you are doing it right.
- its common to do many lap just to tune the camber.

The gearing section should be an interesting one, I also have an excell calculator I use for looking at gear ratios and there effects, I have attached it below.

You may want to add tyre diameter calculator using speed data, it makes people who doesn't have the car data can use this too (or maybe we can measure the tire using photomode, do we?). So, we just drive the car at 2nd gear, enter the speed, enter the rpm, enter the 2nd gear ratio, enter current final drive, and we will have the tyre diameter.

So, I mixed up tyre diameter with wheel diameter .

I use goal seek to find the gear ratio.

 

[Scaff]

@sucahyo

And I thought my methods for tuning took time, fair play to you for the amount of work you put in.

Not sure if its a method I would use myself, but the world would be a boring place if we all did things the same.

Your tyre calculator is interesting, I would say however that I would not recomend using photomode to try and measure wheel diameter. The lack of an accurate scale would make this very difficult and even a small in-accuracy would throw the figures right out.

I've always found that any of the information regarding tyre and wheel sizes can easily be found using google, all you need to do is remember that its the driven wheel info that you need.

Regards

Scaff

 

[sukerkin]

I have nothing substantive to add to this that Scaff hasn't already covered (familiar story there for me ) but I do want to commend Sucahyo for the value that his work brings out.

I know that some of it is ground that we've all covered before and that some of the sources being dug up are ones we used back when GT2 was new but the 'new eye' on 'old news' can sometimes reveal things that we older hands missed (or at least make us reiterate the rationale behind what we now take for granted).

So keep on working, my friend. It is appreciated.

 

[sucahyo]

Not sure if its a method I would use myself, but the world would be a boring place if we all did things the same.

Yes .

Your tyre calculator is interesting, I would say however that I would not recomend using photomode to try and measure wheel diameter.

I see. Using speed to get tyre diameter and use it to get another speed is fairly accurate though, I get 346mph when trying to aim 345mph on my R92CP (it wheelie though ).

So keep on working, my friend. It is appreciated.

Thanks .