18x10 & 18x12 or 18x9 & 18x11?

[67zo6Camaro]

I know it can be tuff getting that final fit and look. But you do have one advantage over most.... your car has not been painted yet and you can adjust were needed.

Basically all combos will eventually rub depending on how low you want the ride and how hard you plan to push the suspension under load. I would just start with the combo that is "The Look" you want, then adjust the wheel wells as needed.

An 18x10 and 18x12 is a good starting point, as most tire sizes we are currently running will ask for a wider rim. Exp... 275 wants a 9.5 rim and you could push it to a 295 on a 10 wide rim. As for the back.. the 11" wide rim is good for most 305 to 325 set ups but if you have the room to run the wider stuff like a 315 to a 335 then the 12 in wide rim is more in the range of the tire manufactures spec. The manufactures base the rim width on how the tire will shape when put on that size rim. Try to stay within their specs.

So bottom line here get the bigger rim set and do some mock up without the coil-overs in. Push the suspension all the way through the motion cycle and make adjustements in the inner wheel wells as needed.

One other thing, looking at most of the big name builds (Tuckers, Finch, Penny, OLC....) they have all had some type of rubbing during extreme driving conditions. Typically they will make adjustments in the Coil-over height depending on the track conditions expected.

Just keep in mind you have the advantage of makeing the clearance now (before paint) in order to get the look and tire size you want.

Thats my 2 cents.

(edit) just my opinion, if you go to the 19" tall rim, then you add the issue of needing more wheel well clearance as you lower the car. However if you are not concerned as much with the low-ness and are going more for the tire tucking look then it's not as much as a big deal (the 19" will require more work to get low and have travel clearance under extreme driving conditions).