DudeWithAVette

Just blew one of my rear 305 RE71rs driving to an event. I was planning on trying a different tire setup next season but now my hand is forced.

I'm out of A street so I can run any 200TW tire. It looks like the Rival-S is the Corvette go to as they offer 315 and 335 18" sizes. This tire setup will see about 6 HPDE days per year as well.

Couple questions:

Do the 315s really fit on the stock 18x10.5 c5 wheels? That seems like too much tire for the wheel.

Has anyone run a 335 square setup in a C5? What wheels are recommended? Any rubbing? Any active handling problems?

315 square seems to be pretty common at events. I'd like to run 315/335 or 335 square if it is doable. It be nice to only have to buy two more 18.x10.5 rear wheels instead of a set of four new ones but if 335 square is possible it might be worth it.

Frank O'Brien

I run HPDE' S on 315/30's Hoosier R7's on C5 Z06 wheels for a square set up on a base model C5. Car is lowered maybe 1.5" all the way around with coil overs on front. I just installed rear Z06 brake cooling ducts and they rub with 1/8th" spacers. Any more than 1/8th spacer and the hub's hub centric lip will not carry. I run long ARP wheel studs but not willing to track car without hub centric set up. Street set up I run half inch spacers on 18" square 275's to clear my Brembos up front. Going square is expensive but I think worth it. Good luck.

DudeWithAVette

That good info thanks Bryan. If Hoosiers fit the Rivals should no problem.

Acid666

I just finished mounting a 315 square setup. Fits fine, doesn't see any rubbing anywhere so far. I thought it would rub at full lock left/right or turning on curbs but I haven't yet found it to hit anything. Front sticks out a little bit. I'm lowered 3 threads from the bottom of the stock bolts.
The tires fit fine but do extend a little past the lip of the rim. I sized it up with my 305/30/19 RE-71s and the Rival-S 315 is about the same width, likely due to being pinched on the 10.5 rim.
A friend of mine is currently trying to fit 335s on the front of his C5 with an 18X12 rim. If he gets it I'll let you know.

l98tpi

Majority of the fast cars in CAM S are running 315/335. Not saying you have to go to this to be fast but just that most are running the 315/335 set up. There are a few talking 335 square. But haven't seen that ran yet.

eric1855

335 up front would take some work to make happen. Not 100% sure it'd be faster with a Rival, seems like you'd lose even more feel and the Rivals are vague enough as is.

When I was on essentially stock power I liked the 315s square, plenty of grip and it was nice to be able to rotate. Now though, with a lot more power, 335s out back are great, not necessary, but are notably quicker.

There is way more to it than just tires though...suspension set up, alignment, etc will all play a factor in what setup works better for you.

Personally I run 315s up front on 18x11s and 335s out back on 18x12s.

a_ahmed

Funny you guys mention this, there was a video that surfaced on youtube about a stock c5 z06 vs a brand new mustang gt350, the stang was faster, but, given R888s and 315/335 setup, the stock c5 z06 handled and gripped and lapped as good as the new gt350. And there are better tire choices than the r888 out there.

I wonder if a 19x10 305/30/19 (c6z replica) would work up front...

mattastick

335 on the front of a C5 seems very counter productive. My car with 11s in STU trim (the same wheels I'd run in the front for a CAM-S build) is already really wide. I wouldn't want to add another inch of front track width, plus the tires. That seems like a poor decision.

In CAM, as with any autocross class, the most important thing is the driver anyway. Which is why you can see AS cars finishing near the top of the heap in CAM-S, when they're well driven.

The 305/19 is really tall, IIRC, and doesn't provide a significant advantage as far as I can see, over a 315/18 Rival S. If I'm building a C5 for CAM-S, I'd run Eric's setup exactly: 315/11 front, 335/12 rear, Rival S tires, wheels of your choice. That's a proven setup until something comes out that's faster, so focus on the rest of the car/driver combo.

a_ahmed

ah i was just wondering because i have 19x10 and 305/30/19 and was intending to get 305/30/19 for the rear :/

Chets LS3

Chets LS3

jcarothers

I run 315s squared on my car. I don't see the NEED for 335s in the rear. With a ton of power, I could see maybe wanting a bit more rubber, but how much power are you really trying to put down in an autox car?