What size tires for C6 rims on a C5?
 

Non-Z C5. I will be slapping some base '08 C6 rims on the car. What size (front & rear) should I go with/can I get away with that will not interfere with active handling & such as well as not cause the speedo to read too much lower/higher than I am actually going? Also, I will be lowering the car some on stock bolts.

I'll be looking to put some good summer tires up front & either same rear or perhaps R888 or something else that helps with traction, but still lets me turn. (600+ WHP)

I am using stock C6 sizes. 245/40R18 front and 285/35R19 rear. Are you planning on running any spacers?

I wasn't planning spacers. Do I have to?

You'll probably want some spacers for the rears, at least. When I bought the car, it had 1/4" spacers in the rear, and the wheels still looked tucked in and were rubbing on the parking brake cables. I switched to 12mm spacers with extended lug studs and now everything clears and it looks better. Some people run a spacer up front too but I think my car looks fine without anything in the front.

Now I also need extended lugs? Too much of a hassle

Some people also use adapters, but those push the wheels out farther toward the fender lips; too far for me. I'm not the only one running base C6 wheels on a C5, I'm sure you'll get some more input from others.

1/4 inch spacer and extended lugs on mine. Otherwise the rears will rub when you go over bumps. The person I bought the car from didn't put the spacers on I kept smelling burnt rubber after coming home from work. Took tires off and you can see the rub marks on the tires.

I searched here and people said 1/4" in back and extended lugs. No smell since then and no rub marks.

I run the N73 option. They look great.

I went with stock C6 sizes. 245/40R18 front and 285/35R19 rear
I also purchased a pair of adapters. Only needed them for the rear.

https://cimg5.ibsrv.net/gimg/www.cor...df88e659aa.jpg
A little Blue Loc-Tite on the OEM studs, and torqued the adapters to 100 ft. lbs. Had to trim off unthreaded portion on each stud. Cut off wheel made quick work of it.

https://cimg9.ibsrv.net/gimg/www.cor...a3db5ef022.jpg


Wheel installed, looks pretty good to me, I'm happy.

https://cimg6.ibsrv.net/gimg/www.cor...d0084ef4a4.jpg

https://cimg8.ibsrv.net/gimg/www.cor...b1ad8cda08.jpg
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Looks good. Do you happen to have links?

Got then from a local forum member .
You can find them on Amazon.... do a search, Hubcentric Wheel Adapter 5 x 120.7 is the bolt pattern, 20mm is the thickness and the 70.3mm is the center bore.