67 camaro front backspace help

[Easytouring831]

Hey guys building my first car at the ripe age of 20 and could use a little help. So a little back info, I ordered my rear wheels the other day and tires, I'm going with 18x11.5 with a 315/30/18 rival tires with a 5.2 backspacing. The fronts I haven't ordered yet due to my backspacing question. It's a stock subframe and I was shooting for a 18x8.5. I'm running 4th gen camaro ls1 brakes. My other question was tire size for the front. From my calculations to have the front and rear sidewalls relatively close id have to get a 235/40/18. Does this sound about right ? Thanks for all the help. Below are the bf goodrich rivals I got form tire rack. Received them the day After ordering, awesome service. Also the rims I'm going with, weld rts

[mikewoods]

Those wheels look great!

I have ls1 brakes on my 68 firebird and used 245/45/17 with 5.15 backspace on a 8 inch wheel on the front. My tires are tucked under the fender and it doesnt rub lock to lock. Of course, your mileage may vary.

[Easytouring831]

Thanks for the info mike. Do you think you could fit a 8.5 width wheel under there and still have the tire tucked? The wheels have an option for 18x8.5 with a 4.6 backspace, I'm thinking about pulling the trigger on those today