pinion angle and caltracs

[reera]

Hey guys. I've got a question about what you set your pinion angle at when using caltracs. My car is a 71 Pont. Ventura (Pontiac's version of a Nova) with caltracs bars, split leaf mono springs and Calvert's Rancho shocks. It's a 9" tire car set up just like a stocker with a mild 350 bracket motor, with even an old stocker camshaft. I've tried the bars on both holes at different preloads, all shock settings, all tire pressures and still can't seem to get what seems like tire chatter out of it, right after the initial hit. I footbrake the car, stab the throttle, the car jumps like it wants to leave, and then the rear starts shaking (only for a short time). The front end is free, with Afco lightweight bushings, Koni SPA-1 shocks, and Moroso springs. It does get the front off the ground, but it is just a hop before it starts shaking. I normally try to use 1/4 turn of preload in the bars as Calvert suggested, but just for kicks, I put a full turn in one time and it was a totally different car. The front hiked up waaayyy better but it still got to shaking slightly. That led me to believe that the full turn of preload wasn't letting the pinion kick up as much on the launch and that I may have a pinion angle problem. Also with that much preload, I may be "pushing" more downward pinion angle into the rear end. It presently has about 2 1/2 degrees down versus the driveshaft angle. What do you all suggest?

Thanks,
Ryan W.
W316 ET Bracket