A body cars......
I believe A body's are a little easyer to play with. Shorter wheel base....less overhang on both front and rear plays a big roll. When Darren Smith (last years world champ) was building his Dart we went through about four sets of bars and a few others that were home made. ( ) We played with spring rates, tapers and everything that we could think of. We learned that you can not compare the spring rates of a coil spring to that of a torsion bar. I thought that was strange but we came to the conclusion that the length of a torsion bar and length of a coil spring (if you unwound it) plays a big roll in spring rates. The bottom line was.....for a very long time Darren ran the MP .840 bars and they worked very well.