Yes but this thread is meant to be about generic physics regardless of corners, not about driving technique. Since almost every car has a different fastest line through any given corner, it's hard to define exactly where an exit is and what that means, where as I can take any car to a skidpad and say that rear camber helps/hurts under braking and helps/hurts on power.
So you don't know where to exit, so you don't know that it means on throttle out of a corner?
So I ran some laps of Willow Springs with one of my tunes to look at in the new datalogger. I compared a lap with 0.0 camber front and rear and then a lap with 1.0 camber front and rear. One thing that confused me was in the data logger the car with 1.0 camber had consistently higher wheel speed on all 4 wheels compared to the 0.0 camber car. It was about 20 units higher stayed 20 units higher on straights and through corners. The lines were pretty much parallel the entire lap. I have no idea what this means. Maybe someone with a little more knowledge can explain to me why wheel speed is higher with camber, or maybe it was just a glitch. I didn't have much time to do anything else but may come back to this later tonight.
yep yep 0.0 camber was faster by about half a second around Big Willow. I feel I should qualify that with the fact I did 2 laps with each set up, this was the first time I ever drove the car with any camber, and the car was tuned for 0.0 camber.
My guess is that you found higher wheel speed because, as you add camber there is less of a contact patch between the tyre and track surface meaning less friction and more slip from the tyres, this would also help explain the drop in lap time as you would have had less grip with the camber added. So I would say that the camber issue is still the same as it was pre update 1.06 going by this data. But I'm just an amateur, what do I know.
I see some improvement in lateral G during cornering but significant wheel slippage on acceleration. So possibly camber may prove a bit useful on a non driving axle in small amounts. Like a RR, MR,or FR with understeer or FF with overseer. Otherwise I see little benefit from its use.
. And please excuse me for my poor English.
Hi guys. New here so please don’t be rude
After going through this post I’ve realized about some statements showing the idea that more contact patch from the tyre in touch with the road means more grip, but as far as I know this is not true at all. In fact, the grip should be exactly the same, being the benefits of a wider contact patch others such as better tyre cooling or slower tyre wear.
I’m not that physics genius, so I’m going to quote “Friction” from Wikipedia:
“The static friction force must be overcome by an applied force before an object can move. The maximum possible friction force between two surfaces before sliding begins is the product of the coefficient of static friction and the normal force: Fmax = m· F. When there is no sliding occurring, the friction force can have any value from zero up to Fmax. Any force smaller than Fmax attempting to slide one surface over the other is opposed by a frictional force of equal magnitude and opposite direction. Any force larger than Fmax overcomes the force of static friction and causes sliding to occur. The instant sliding occurs, static friction is no longer applicable—the friction between the two surfaces is then called kinetic friction.
An example of static friction is the force that prevents a car wheel from slipping as it rolls on the ground. Even though the wheel is in motion, the patch of the tire in contact with the ground is stationary relative to the ground, so it is static rather than kinetic friction.”
This means that how big the contact patch is doesn’t affect when it comes to prevent the tyre from sliding. It makes sense, as the only involved parameters are “m” -mu, the tyre grip, softer tyres have more while harders have less- and “F” -the weight the car loads into the wheel in each moment-. A bigger contact patch means that the weight is divided between, lets say, more squared millimeters, so every one of this squared millimeters is less effective. If the contact patch were just 1 squared millimeter, all the weight would press in that point, making it really sticky. Summarizing: as the formula shows, the area in contact is not a variable when it comes to find out how much lateral force is needed to make a turning tyre slide out in a curve.
I know what comes next: Then why almost every racing car is set up with negative camber on it’s wheels?
I think that there are 3 main reasons, all related to curves:
1) More stability when getting into a curve, as the outer tyre stays perpendicular to the road thus it’s shape is maintained.
2) Letting the contact patch of the outer tyres roll parallel to the road in curves makes it wear uniformly, causing it to last longer. Otherwise only the outer band of the contact patch would wear, making it’s rubber go away earlier and thus the tyre become unuseful earlier. When the rubber has gone away, the grip falls down.
3) Negatively-cambered wheels heat uniformly when stressed through curves, so the temperature increase is uniform in the whole contact surface. In a non-cambered wheel, the inner band would stay cool as it’s not in contact with the road but the outer band would be overheated, causing the rubber of the band to cook and thus to deformate, ruining the tyre earlier than expected. When the rubber is deformated, the grip falls down.
On the other hand, all that said becomes an against when talking about straight line driving. The balance is the key, so I think that finding this balance should be the starting point when looking for the fines camber value.
That was the way I think real life is. Now back to Gran Turismo. As far as I know, only stability is implemented in the game. I might be wrong, but I reckon that non-uniform tyre wear and deformation caused by overcooked local tyre areas are not implemented so far.
In conclusion, I think that in GT, in certain situations some negative camber in the front wheels should cause more stability then turning in, what is good, but never more grip and thus never higher speed through curves before sliding out.
Now please let me say that my previous statement doesn’t mean that I don’t think the programming of the camber in the game is a complete mess…
Hi guys. New here so please don’t be rude
After going through this post I’ve realized about some statements showing the idea that more contact patch from the tyre in touch with the road means more grip, but as far as I know this is not true at all. In fact, the grip should be exactly the same, being the benefits of a wider contact patch others such as better tyre cooling or slower tyre wear.
I’m not that physics genius, so I’m going to quote “Friction” from Wikipedia:
“The static friction force must be overcome by an applied force before an object can move. The maximum possible friction force between two surfaces before sliding begins is the product of the coefficient of static friction and the normal force: Fmax = m· F. When there is no sliding occurring, the friction force can have any value from zero up to Fmax. Any force smaller than Fmax attempting to slide one surface over the other is opposed by a frictional force of equal magnitude and opposite direction. Any force larger than Fmax overcomes the force of static friction and causes sliding to occur. The instant sliding occurs, static friction is no longer applicable—the friction between the two surfaces is then called kinetic friction.
An example of static friction is the force that prevents a car wheel from slipping as it rolls on the ground. Even though the wheel is in motion, the patch of the tire in contact with the ground is stationary relative to the ground, so it is static rather than kinetic friction.”
This means that how big the contact patch is doesn’t affect when it comes to prevent the tyre from sliding. It makes sense, as the only involved parameters are “m” -mu, the tyre grip, softer tyres have more while harders have less- and “F” -the weight the car loads into the wheel in each moment-. A bigger contact patch means that the weight is divided between, lets say, more squared millimeters, so every one of this squared millimeters is less effective. If the contact patch were just 1 squared millimeter, all the weight would press in that point, making it really sticky. Summarizing: as the formula shows, the area in contact is not a variable when it comes to find out how much lateral force is needed to make a turning tyre slide out in a curve.
I know what comes next: Then why almost every racing car is set up with negative camber on it’s wheels?
I think that there are 3 main reasons, all related to curves:
1) More stability when getting into a curve, as the outer tyre stays perpendicular to the road thus it’s shape is maintained.
2) Letting the contact patch of the outer tyres roll parallel to the road in curves makes it wear uniformly, causing it to last longer. Otherwise only the outer band of the contact patch would wear, making it’s rubber go away earlier and thus the tyre become unuseful earlier. When the rubber has gone away, the grip falls down.
3) Negatively-cambered wheels heat uniformly when stressed through curves, so the temperature increase is uniform in the whole contact surface. In a non-cambered wheel, the inner band would stay cool as it’s not in contact with the road but the outer band would be overheated, causing the rubber of the band to cook and thus to deformate, ruining the tyre earlier than expected. When the rubber is deformated, the grip falls down.
On the other hand, all that said becomes an against when talking about straight line driving. The balance is the key, so I think that finding this balance should be the starting point when looking for the fines camber value.
That was the way I think real life is. Now back to Gran Turismo. As far as I know, only stability is implemented in the game. I might be wrong, but I reckon that non-uniform tyre wear and deformation caused by overcooked local tyre areas are not implemented so far.
In conclusion, I think that in GT, in certain situations some negative camber in the front wheels should cause more stability then turning in, what is good, but never more grip and thus never higher speed through curves before sliding out.
Now please let me say that my previous statement doesn’t mean that I don’t think the programming of the camber in the game is a complete mess…
.
Well, that part about how the presure is divided by the wole surface is obviously not for a nobel prize. It's better explained here:
