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Old 04-14-2016, 10:28 AM   #1
xnamerxx
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Quote:
Originally Posted by cyberguy View Post
Because the side walls of the tire are harder than normal tires, it provides a better feeling but not less grip. Basically R1R are excellent in handling. Is that what you meant by "unloaded"?
It has nothing to do with the tires per se, basically FWD cars have a stiffer rear frequency than front. So whats happening, when you go into a corner, the outside front takes the load\(some people find it easier to use the term weight) and the outside rear loses its load\weight. Well enough load is transferred quickly enough and for enough of the front suspensions travel, you'll end up picking up a rear tire. So the more "grip" you give the car the more it'll pickup a rear tire, since the outside rear tire isn't really doing anything it generally doesn't hurt much.

The other issue that "could" be at play, is stability control is apply brakes to the rear of the car which will also cause a rear tire to lift. Rear suspension generally has quite a bit of anti-lift built into it, so when torque is applied to the suspension(hitting the brakes) the rear of the car will want to squat down. A easy way to test this is to put the ebrake on and gently try to move forward, you'll feel the rear squat down.

I don't fight rear tire lift on my road race car, its generally just something you have to deal with on FWD cars.
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Old 04-15-2016, 05:52 AM   #2
cyberguy
 
Drives: d4d
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Originally Posted by dragoonmc View Post
I'd upgrade the front sway at to a bigger one which should help keep the front of the car flatter and might level out the rear. Otherwise figure out how to turn off stability control
the front sway bar is a great idea. I know how to turn off TCS, unfortunately you need to do this each time you turn on the ignition and there is no button to manually enable/disable it.

Quote:
Originally Posted by xnamerxx View Post
It has nothing to do with the tires per se, basically FWD cars have a stiffer rear frequency than front. So whats happening, when you go into a corner, the outside front takes the load\(some people find it easier to use the term weight) and the outside rear loses its load\weight. Well enough load is transferred quickly enough and for enough of the front suspensions travel, you'll end up picking up a rear tire. So the more "grip" you give the car the more it'll pickup a rear tire, since the outside rear tire isn't really doing anything it generally doesn't hurt much.

The other issue that "could" be at play, is stability control is apply brakes to the rear of the car which will also cause a rear tire to lift. Rear suspension generally has quite a bit of anti-lift built into it, so when torque is applied to the suspension(hitting the brakes) the rear of the car will want to squat down. A easy way to test this is to put the ebrake on and gently try to move forward, you'll feel the rear squat down.

I don't fight rear tire lift on my road race car, its generally just something you have to deal with on FWD cars.
You verify what I thought was the problem, it is not a tire problem but better traction amplified the problem with the rear axle. This is the first time I own a "fast" fwd car and I am used to my subaru Sti (track day car) which has a different philosophy.

So one solution, which dragoonmc suggested, is to upgrade the front sway bar. What do you think will happen if I buy a proper coilover (bilstein pss) or kyg agx with eibach springs?

I believe that the front outer suspension will have less compression than the stock one, so the rear will be lift less, so the inner rear wheel may not lift at all, so the traction control will not be activated.

Do you agree or not? please elaborate.

Last edited by cyberguy; 04-15-2016 at 06:02 AM.
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Old 04-15-2016, 11:57 AM   #3
froger
 
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How long have you had it on.?Some of the newer systems have a learning ability,so you might have to drive it for a little while before it becomes less
intrusive and learns how you drive.But it might just mean that you are pushing the car to the limit and it is detecting a bigger slip angle between your input and what the car is actually doing.(under steering)I would try a rear sway bar on the rear so the back loses traction first ,canceling the under steer.Right now it seems like your front tires are losing traction first causing a under steer issue , meaning you are turning the steering wheel more to compensate and make the car turn the direction you want to go.By adding just a front sway bar you just adding to this problem by making the front tires lose traction even faster .
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Old 04-15-2016, 06:08 PM   #4
cyberguy
 
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Quote:
Originally Posted by froger View Post
How long have you had it on.?Some of the newer systems have a learning ability,so you might have to drive it for a little while before it becomes less
intrusive and learns how you drive.But it might just mean that you are pushing the car to the limit and it is detecting a bigger slip angle between your input and what the car is actually doing.(under steering)I would try a rear sway bar on the rear so the back loses traction first ,canceling the under steer.Right now it seems like your front tires are losing traction first causing a under steer issue , meaning you are turning the steering wheel more to compensate and make the car turn the direction you want to go.By adding just a front sway bar you just adding to this problem by making the front tires lose traction even faster .
Unfortunately the traction control does not have any learning capabilities. I have been racing for many years now and when I say that the car does not understeer I am certain 100%.

The problem exists because the inner rear wheel is raised from the ground and the traction control is activated due to the difference of rotation between the two rear wheels. I am certain of this, as I have even installed a gopro in order to verify it. Of course this does not happen in normal driving but not in extreme conditions too. If for example normal speed for a turn is 90km/h and extreme speed is 140km/h, the issue appears at 100-110km/h
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