RaleighSS

I have done a bit of research and came up with some basic info but still not clear of the pros and Cons of running all 17" on a C5 Z06. Tires are a bit cheaper .... and seems if you do the right sizes you can keep the rake the same .... what is the cons?

Olitho

Some limited ability to put large rotors and big brake calipers on the front.

RaleighSS

No plan to do that ... will stick with stock for quite a while..

drivinhard

If you are doing DE's, a great budget route is a square set of 17x9.5 C5Z wheels using 275/40/17. Popular size to find scrubs, fits very nicely on a 9.5" wheel.

A lil' sidewall is a good thing

longdaddy

slight difference in the shape of rear contact patch, given the same tire pressures. not sure if you will even feel that unless you are already at 11/10th

RaleighSS

yes only dooing DE here... Should I go with same tire size all the way around or go larger in the rear ?

drivinhard

either or

it's nice to be able to rotate to all 4 corners though

square will usually take some of the factory built in understeer out of the car

Greywolfe

Seems to work very well.

Car rotates much nicer in tighter turns. No more push. This is going from street tires in stock sizes (C5Z) to 275/40/17 square.

Just be aware you have increased your F/R grip ratio and adjust accordingly with your right foot.

Oh yeah ... forgot to mention the 17's were Hoosier A6's!

I could see where it would be nice to have a bit wider in the rear to get the power down on exit though...

RaleighSS

If i went with 17" same size on all 4 corners would my rake front to rear stay the same as with the stock 17/18 combo?

Greywolfe

No. You will lose the rake but honestly I could not notice any difference. I was only getting up to about 110 so at faster speeds maybe you will lose some stability.

You can always get the rake back by lowering the front a bit with the bolts. I think the stock rake is something like 4/10ths of an inch lower in front than in back but I'm not sure.

I just double checked you will lose 4/10 ths of an inch of rake from the wheels if you go from 265/40/17 front, 295/35/18 to same size tires on all 4 corners. They may still be some more rake built into the suspension (which can be adjusted.) This is solely based on tire radius.

drivinhard

heigh difference on F/R tires on stock C5Z is .8", which means half that when on the car. so .4" difference if you go square, not a big deal IMHO

davidfarmer

I agree with above, the rake doesn't seem to matter as it is very minor over the wheel-base. I've run both 275front/315rear and 315 all around setups and both work well. My current NASA setup is 315x18'x all around on identical wheels, as that allows for infinite tire rotation.

I can find used Pro tires easier in 18" sizes, so while new 17"s may be cheaper than new 18's if you are into buying scrubs, 18" is currently the sweet spot.