Can I fit a wider tire than a 235/40/17 on a stock '97 m3 without a fender roll? They will be mounted on 17x8's 35ET and I would like to go with a non-staggered setup. I'm not worried about fitting on the wheels, just want to know if I can go wider and not rub. And I know the rears will be ok wider, but at what point do the fronts rub? The tires will be primarily for autox.

The 35 mm offset moves the front wheel out so that the inside is in the same place as stock and the outside lip is moved out 12 mm. The inside of the rear wheel is moved out 12 mm and the the outside lip is in the same place as stock.

thanks,
\\\wes

Yes. Try a search for info on specific tires and sizes.

I did. On this and the wheel and tire forum, and just haven't found the specific info. Mostly discussion on whether or not someone should run r-comps. I just need to know how much extra tire will fit without rolling fenders, spacers, or rubbing.

I'm looking at Toyo Proxies RA-1s in a 235/40/17 but would consider a different tire if 245's would fit.

Thanks,
\\\wes

I just need to know how much extra tire will fit without rolling fenders, spacers, or rubbing.

Depends very specifically on the tire, your suspension, your ride height, and your wheel offsets. There's no one answer.

In general, a 245 street tire should fit fine all around without mods. A 245 R-comp will generally run wider and may rub depending on your wheels and suspension settings.

That is why I am asking in a forum instead of just using non-specific search information :) The car is completely stock; the wheels are 17X8's with 35mm offset. Where might I find good info on fitment?

Again, I am considering Toyo RA-1s which come in a 235/40/17 or a 255/40/17. I do not think that the 255 will fit (at least up front). I am really concerned about running a 245/40/17 (say Kumho V700) on the front. At what point does it rub?

Does anyone run an m3 in autox (I am in SCCA B Stock) and have a good setup to recommend?

That is why I am asking in a forum instead of just using non-specific search information :)

Then perhaps the specifics of your tire options would have been a good idea to include in the original post? :stickoutt

Running in stock class, my educated guess would be that a 245/40 Kumho will work. I doubt anything bigger will fit up front. You may still need a small spacer to prevent the wider tire from rubbing the strut. If you want to be somewhat competitive in auto-x, stay clear of the Toyo's...they'll never heat up enough to be useful. Also, are 17x8 wheels legal for BStock? I don't think the M3 ever came with 8 inch wheels.

Brian's right - to remain in stock you need the same size wheels as the car came with, 7.5s and 8.5s respectively.

I think 35mm with an 8" wheel is a little too small an offset. The stock rears (17x8.5) fit in the front with 245s on them typically, but they're 41mm offset; more room.

I had to flatten the lip of my front fenders to fit 245s with 8" et 37 wheels and 3.5 degrees of negative camber. You might want to compare the section widths, I'm guessing the wheels you have would be pretty darn close with 235/40s...but it'd be mighty close.

Yeah, you guys are correct that the wheels would bump me from stock. And I know that the Toyos are not going to be a great autox tire, but I also want to put a track day or two on them, so they are a compromise (cost and usage). I am still learning to drive the car and having the most competetive tires is not a big concern yet. I have autox-ed for a few seasons, but this is the first in the M3. That said, I do want to make the best of the set up to prepare and learn for the future. I appreciate your help.

\\\wes

The Kumho Victo's would be a good trade-off between auto-x performance and holding up to some track usage. I never found their wear to be all that bad when I ran them on my old 325.

Generally, et30-35 is ideal for max front tire fitment, depending on the camber you run. 235/40's on 17x8 et35 will clear easily. A 245 should also clear.

With -2.7 camber up front, I have run 255.35 r-comps's on et45 18x9's with a 15mm spacer (net et30) and zero rub.

With stock camber, I have run 245.35.18's on 18x8.5 et38 with zero rub.

I was able to run 245/40/17 on the fronts without issue...on stock offset. I also had some FIKSEs with stock offset and ran the 245s on them too.

I just went to 245s all around with 15mm spacers in front due to shock towers rub. I rubbed in hard turns,I have Bilstein sport shocks and bavarian springs, I rolled the fenders a liltte and lossened the fenders ,pulled them out and retightened them and was able to get a couple more mm doing that, now I have no rub.
235s in front is pretty safe in most cases but beyond that you will probably have to make some adjustments like I had, was no big deal, good luck

i am running 255/35/18 all around on 18x9 ssr comps 45 offset. w/ a 15mm spacer up front to clear the bilstiens i only rub under heavy load. i have just ordered a ground control setup to utilize the koni's strut houseing as they are narrower than the bilstiens and will pull the wheel in a little to clear under load. you can fit a lot of tire under a stock front fender.

GC has taken two months to get my kit and i will not recieve it till next week. i am extremely pissed about this. has anyone else experienced this from GC?