Actually, to keep the wheel/tire centered within the factory wheel well and, most importantly the on-center track width, the correct BS for a 9" rim is 5", then a 10" rim is 10.5".
Mopar Mitch
"Road racers and autocrossers go in deeper and come out harder!"... and rain never stops us from having fun with our cars... in fact, it makes us better drivers!
Check out MOPAR ACTION MAGAZINE, August 2006 issue for feature article and specs on my autocross T/A!
