Im sure this has been discussed many times but the search thing sucks so much. It wont let me search for anything less than 4 letters (stupid). Anyways, I have a 550hp 540tq SBC, yes its cammed to all hell but you gotta love that lopey idle. Anyways im wondering if I should stick with the 10 bolt posi with 3.73 gears in my '72 3500lb chevelle. The axles are 30 spline and are pretty heavy duty. Or should I go with a 12 bolt? In case you were wondering Ill be doing mostly street driving and going to the strip with slicks on over the weekends. Thanks guys.