proorange

Is their a general rule of thumb on tire height difference front to rear so not to cause the ABS to act up?

RicK T

Disclaimer: I'm not smart enough to know this on my own. I copied it from a discussion in the Z06 Forum, posted by CGZ06.

General rule:

Racingswh

I have run way taller in the rear 27.95" to 25.4 " front which is greater than anyone would recommend without any issues. Make sure the rear tire is taller the front. I did it for 2 track seasons on Continental slicks. Never a problem of any kind with TC on or off.

dentalfloss

I am with you on this question. I have stock size tires and when I get up to 90-100 mph my ABS, active handling and traction control light come on. I can run hard through the gears up to that mph or slowly creep up in 6 gear and the lights come on. I have been told to go into diagnostics and check your programed tire sizes. I bought my car used and who is to know if someone messed with that. So if a tech goes into diagnostics, what should he look for or program size wise.

Kent1999

For typical C6 sizes, the rule of thumb is to have the rear tires 1" taller than the front tires. (tire *width* doesnt matter to the ABS/TC systems -- only diameter)

Rick T's quoted formula is probably accurate as well... for typical C6 sizes it works out about the same... 1" difference f/r.


Cheers,
Kent

proorange

Thanks for the info guys.

HOXXOH

To assure you are within the OEM programmed limits do this simple math.
Circumference of new OEM front tire = A
Circumference of bald (0 tread depth) OEM front tire = B
Circumference of new OEM rear tire = C
Circumference of bald (0 tread depth) OEM rear tire = D
A/D = Maximum f/r ratio
B/C = Minimum f/r ratio

If the new non-OEM tires fall inside the ratio limits and wear evenly, Then AH will not be affected.

cclive

Revolutions per mile is a nice easy number to use in comparisons...and more accurate than a measuring tape used to measure the height of the tire. Tire Rack gives the revs/mile stat for many tires on their site.