Gn Wheel Backspacing

[marred4life]

I LOOKING TO WIDEN MY STOCK WHEELS TO ABOUT 9" BUT I WANT TO KNOW THE CORRECT BACKSPACING FOR RUBBING CLEARANSE, I RUNNING 275/50R15 BFG RADIALS.

 

[dsa87gn]

I had mine widened to 8" with 4" BS.
I have 275/50R15 BFG Drag Radials on mine that fit fine

 

[49-blues]

I have a refinished set of 8.5" with a 4.25 bs fit and look great for sale with no street time or track time unused and in the garage-i paid about $550. with the cores from "G"Body Parts-will part with them for $450. shipped. I have 275x60x15 hoosier quick time pros on the right now- could send pics this weekend.