JohnAlley

I plan on running a squared set up on my 2000 FRC dedicated track car. I want to run 10.5 width , what wheel offset do I need to make sure everything fits front and rear?? I am also planning on a brake upgrade to Stoptech or Wilwood big brake set up so what size wheel should I plan on?

gmccreary

Stock C5Z 18 x 10.5s work fine on all 4 corners. No mods required.

geerookie

That is a 58mm offset and works with up to a 315/30-18 square setup. You may need a 1/8" spacer to clear some of the larger brake calipers and will need to run at least -2.5 degrees of camber to clear the front fender lip.
63mm also works depending on what size tire you run and how much camber you have.

Bill Dearborn

I ran 4 C4 GS 17x11 wheels with the LG G Stop kit with no spacers. When I went to 4 C5Z 18x10.5 wheels I had to run an 1/8 spacer to be on the safe side. The wheel cleared the caliper by a whisker but if there was any movement in the bearing or flex in the wheel during hard cornering it might have touched the caliper so I put the spacer in. The LG kit is nice because it lets you use the wide SL6 calipers with the thick pads while still fitting everything under a stock C5Z 17x9.5 front wheel without any spacers.

Bill

drivinhard

also note the caliper clearance is more than just offset, it's how the wheel is designed and shaped (spoke to caliper clearance). the SL6's will clear the 17" C5Z front wheels because of the shape of the spoke is different where it's near the caliper vs the 18" wheel. If you put the same caliper on a bigger rotor (closer to the barrel) the 18" would clear fine with no spacer.

Both have the same distance from the rotor face to the outside of the wheel. The 18" have different offset which puts the extra 1" of wheel width on the inside of everything.

It's hard, very hard to beat the rear C5Z wheels for weight for the same size, it's impossible at the (used) price point