295 tires - 9.5" vs 10.5" wheels
 

Today I had Michelin Pilot Supper Sport 295/35/18's mounted on my C5 wheels. I'm using 4 factory "rear" 18x9.5 wheels (powder coated matte black) on the 4 corners. The ride, handling and look is significantly better. As a bonus, it seems like this setup will give much better protection from rim damage (curbs, rocks, potholes, etc.).

Regardless, I feel the need to ask:

What advantages (if any) would I gain by moving up to 10.5" width wheels? When I look up the specs for the Michelin PSS's, they call for 10"-11.5" wheel, with the measured width being 10.5" (e.g.: C5 Z06 factory rear wheel).

Supposedly, a wider wheel gives you a less rounded tire, ie.. a more square tire which is supposed to give you more traction because it creates a wider contact area. My personal thought is that it really doesn't make that much difference. Your question... 9.5 up to 10.5. You'd gain 1/2" on each side. How much more contact patch would you have over the 9.5? Probably not very much, but a little. I'm personally running 325/45/17's on 17x9.5 wheels on the rear of my big HP car. They hook good. Everyone would say I can't do that, but yes you can. Hope that helps.

YIKES! That's a lot of tire on a 9.5" (never would have thought you could get away with that). Thanks for the feedback. :)

They're also 28" tall. 1.5" taller than stock size tire.

https://cimg9.ibsrv.net/gimg/www.cor...eeab088bb9.jpg

https://cimg0.ibsrv.net/gimg/www.cor...cc21c4acc3.jpg

Couple more. They don't bulge hardly at all, just enough to protect your rim from curbs, plus they don't stick out (well not much).

https://cimg1.ibsrv.net/gimg/www.cor...6ed4fbad36.jpg

https://cimg3.ibsrv.net/gimg/www.cor...e2980a5260.jpg

Cactus, what width wheels are those tires mounted on? I didn't see you mention it.

So you have 4 FACTORY C6 17x9.5 wheels on your C5 with no spacers?

I like it, gives it a racey look.

What is the tire size of the fronts?

I'm running 17x9.5" on the back and 17x8.5" on the front.

Not quite but close. I have 9.5" wheels in rear and 8.5" (stock size) in front. Also, they are C6 replicas in standard C5 backspace sizes (so no spacers needed or used). I bought the car with the same front wheels (17x8.5) and the original rear wheels were 18x9.5". I liked the way they looked so have kept them the same look all this time. Previously, I'd added a set of rear 18x10.5" rear wheels (same C6 replicas in C5 Z06 size) and was running some Toyo Proxes TQs in 315/35/18 size. Those worked pretty well but after putting the LS3 and supercharger in, those just wouldn't hook. So I ordered some 17x9.5" C6 replicas (the ones you see now - they are C5 Z06 front wheel size) and put the 325/45/17s on them. The rear M&H tires are 28" tall while the previous stock size was 26.5" tall. Taller = better grip but that created a problem with keeping tire sizes within the recommended .5 - 1.5" range of front to rear. The factory stock front size is 245/45/17 and that tire was 25.5" tall. I replaced the front tires with some Nitto NT555 G2's in 255/50/17 size which are 27" tall. So I basically added about 1.5" taller in both front and back. They're both a tight fit but work well. I had to adjust the rear coilovers to keep the rear tires from rubbing the wheel well. They rubbed just a little at first but got that fixed pretty quickly and don't have any problems now. I kinda like that "race" look as well. I'm not a big fan of the rubber band tires. I like lots of sidewall. Plus a good benefit of using tires this size is the slight bulge which protects the rims from curb rash. Not every one likes this sort of setup but I just make it the way I like it. I think it looks good (to me anyway) and it has a great ride (all that extra sidewall is nice). Fun to drive on the street and at the track, just drop those M&Hs down to 18psi and get it!

I got to thinking about comparing the way it used to look to the way it looks now. Here's a thread from about 4 yrs ago when I was running the stock 245/45/17 tires on front and had just installed the new Toyo Proxes (315/35/18) on the rear. You can see that the 26.5" tall rear tires don't nearly fill out the wheel well like the new M&H 28" tall tires do. Same thing for the stock 25.5" tall front tires, now at 27" tall.
https://www.corvetteforum.com/forums...s-of-pics.html

When looking at tires and mounting them on wheels, you have to remember what you are going to use the tire for. When I was running Hoosiers, the sidewalls were very flexible and you could mount 315/30x18 tires on stock C5 rears (9.5"). but for daily driving I would not go larger than 275/35x18 tires. For autocrossing I run 275/35x18 Bridgestone RE71R tires and the sidewalls are so stiff you cannot mount them with a single arm tire changer and many of the cheapo double arm changers cannot mount them. For your average street tire you can squeeze on a 295/35x18 tire on the standard c5 rear wheel. If you look at the manufactures recommended wheel sized you will see they have several different widths to choose from. The final consideration is the sidewall aspect ratio. A 45 aspect will give you more rubber to work with to tuck into the wheel while a 25 aspect ratio might require a 295 tire to use a 10.5 or 11" width tire.

315/30 is a short sidewall to run a 9.5.

I did 315/35 17s on factory 17x9.5s on my '93 but would be hesitant to run a 315/30 on 9.5.

The 315/30x18 tire I mentioned is the Hoosier A7, and autocross tire, it has an extremely flexible sidewall, the other tire I mentioned is the Bridgestone RE71R and a 275/30x18 tire is near impossible to mount on a 9.5" rim.