Benton

I'm planning on widening the front wheels on my 928 in the future, but for the time being, I have to go with the 8" for the front. I think a 255/40 will work, but I figured I should inquire here before I purchase. I know people run a 245/40 on 8" wheels pretty regularly. Will I be OK running them?

cstreit

You'll really be pushing the width limits. 245 is about as wide as I'd want to go safely on an 8" wheel. The tire manufacturer has the ultimate say on this and will have a better understanding of the sidewall dynamics. I'd go to their website and find a technical support number.


Chris Streit
MotoDelta Motorsports
Mdwest NASA GTS Director

Geoffrey

An RS America has an 8" rear rim with a 255/40 on it from the factory. I think the tire is better suited to a 9" rim.

Benton

Thanks for the input, guys. I understand that the tire is definitely better suited to a larger rim, but I am trying to go as large as possible on the front to balance out the tires on the 928. Ideally, I would run some huge rubber up front almost equal to the rear, but that will happen when I can put 10" wheels or so up there. I'm just trying to minimize the tire size differential so I don't make the car understeer too much.

Matt Marks

I think it will be fine - however, check the tire manufacturer's website and they will show you the recommended wheel widths for each tire size. Most of them will have a range of about 2 inches in width that they recommend for a given size.

Also, you may want to check the rolling diameter (also on the web site) of the fronts vs. rears as too big a difference may cause ABS malfunctions. People typically throw around a number like 5% or so as the maximum difference you want to have - assuming your car has ABS.

LVDell

Correct me if I am wrong but this discussion was just had recently and the concensus was to (in your case) go with the 245 instead of trying to stretch a 255 on it. Reason? Your contact patch will still be the same and you will probably even have better grip levels with the 245 (in your case).

Benton

Would you happen to know what the topic of the thread was? I did a quick search and couldn't come up with it.

EDIT: found it. Thanks for the pointers, I guess I will go with a 245.