My'37 has a 1979 Trans Am / Firebird 10 bolt rear axle under it. It's the 8.5" ring and pinion axle. There are lots of gear choices with this size axle. I am using a 3.08 with 28" tall tires. 70 + mph is no problem for my 250, it will run all day long at 2400 to 2500 rpm.
I am also using standard 7" wide Chevrolet Rally wheels with a 2" wider fiberglass rear fender. In the last 15 years of having the truck on the road, no ones has noticed the wider fenders!
I did have to remove the spring perches and replace them with 1.75" wide ones from a trailer shop. The late models used wider leaf springs. You will need a different transmission and driveshaft.
Joe
Last edited by Joe H; 08/12/2015 2:06 AM.
