hgerrick - I would have to say that depending on your required spring rate, I would consider two different spring configurations. Mind you that it is dependant on spring rate, how the car is going to be driven and other chassis mods. The first would be a FIA type OR a type of build that Tri-City Competition has used in Mopar since the begining of time. They were the orignal spring supplier to Famed Dick Landy.
BTW, the springs from Tri-City Competition are made by the same exact guy/spring manufacturer that I use for my custom builds. The only thing is.......he's not cheap.
Anyway, either build will eliminate spring wrap so that your pinion snubber no longer hits body.
onovakind67 - 400 ftlbs is required to run the heavier, 260lb and up, FIA springs. However, there is a window of element where a spring will work well with the given spring rate and type of build. If you are out of that window with a given HP/Torque figure, the spring is then effictively either too soft or too hard. Too soft and spring wrap comes into play, chassis bottoms out, understeer become apparent; Too hard and you will just spin the tires and oversteer becomes apparent. Basically, the more power, the more spring you need to control it and functions of suspension geometry.
The partial wrap on the secondary leaf (acting like a traction bar) and the leaf being at a flat static loaded position, the spring has a much higher resistance to the torsional loading from the differential. Therefore with the FIA spring design, much less travel under squat because you are keeping the instant center located better from the increase in torsional resistance on the forward part of the spring. There is also some relation the the front spring rate and the length of the coil in an open measurement....shorter spring, shorter moment angle. Rear CG couple distribution will be less effected by the shorter moment of the front suspension. There is a certain required power level to properly load the spring for it to do its magic without going out of its performance window.
This specifically addresses concerns in road racing.