FlyYellow

i remember reading about the maximum allowable differential in wheel height from front to rear wheels. as i recall it had something to do with the ABD working properly on a c2 (i don't have an AWD).

Someone who remembers that article... would the following be ok?

Front diameter: 24.4"
Rear diameter: 25.2"

Thanks,
Boris

PS I did try to search but couldn't find anything...

lexpilot

Your rears are 103.2% of the fronts. I think the whisper number is a 5% differential creates a problem. My 993 had 235/40 front and 265/40 rear for a difference of 12.7%. Strangely no lights ever came on saying my abd did not work. Previous owner had just installed these before I bought the car which is now gone.

Martin S.

I have an Excel spread sheet where you plug in the tire size, front and rear and it calculates the rolling radius delta. I believe the maximum allowable is 6% front to reat. I had 205/40/17 on front 255/45/17 on the rear and the ABS went off. As soon as I put the factory size tires back on the problem went away and never came back. The delta maximum %age, front to rear, is in the 993 Shop Manual which presently is out of print.

Anybody that wants the spread sheet, send me a private message and your e-mail and I'll send it off to you. It is a lot of fun to see what tire combos will work without shuting down the ABS.