Heres the deal ----355 horse small block, 350 turbo, 9" Ford, 340 positraction gear in a steel 32 cabro. Properly built frame, ch***is engineering x member, coil over rear shocks,dropped beam front w/posies front spring. When you get on it,it scoots--hard--the frame torques, left front up, right rear down AS EXPECTED. However now the right rear coil over is sagging. Going to replace that, but the ride has always been decent with this coil rate, so I really don't want to go much stiffer on the coil. Does an anti sway bar (I believe Ch***is Engineering has one that will work on a 32) help keep the frame level under these conditions? I know---the best solution is stay out of the throttle but THATS not likely to happen. RINALDI
Coil overs give very little roll stiffness. Their stance is where they attach to the frame, not the rear end. I have experimented with rear roll bars. I am now using a piece of 7/8 cold rolled to get enough stiffness. Jack up the front so the rear is the only thing giving roll stiffness and see how bad it is, I would try to get the front and rear somewhat the same with maybe more in the rear so it does not understeer so bad.
Pick - a- part has Ford F150s, they have a VERY useable rear antiroll bar with brackets and all...Hides up in there so you can't see it unless you're looking for it. Cheap. Clean. Sanitary....
Before you get carried away you need to evaluate the frame construction in regard to the rigidity of construction. I think some of your twist issue is with the spring rate on the rear and the action created by the rear locating rods during acceleration. A split spring rate will unbalance the rear loading and an uneven split will cause the radius rods or bars to induce a load as the angle of the rods change as the rear axle wraps with traction. To check for issues with the frame or suspension you need to make some solid links to replace the coil overs at normal ride height, then jack the front axle up at the axle front wishbone or 4 bar mount and look for areas that are flexing. If there is no flex then the issue is with the rear springs. If you think there is an issue with the springs you have other areas to check, the actual spring rate and the shock quality. If the spring heights are not equal when unloaded then you need to get the spring checked for rate load. If the springs are even then you need to check the shock load rate and one is not softer than the other. You will also have to check that the shock mount position is similar side to side as a bent or bowed shock mount will change the operation parameters. Before this gets to long, check this much and report back.
Is your frame fully boxed or just in front and rear of the X member? I had a 34 with that same problem and corrected it by boxing the entire length and added some side supports. Now nothing moves when you fall asleep on the right foot.
Or do it the old fashioned way and instal a lift bag (the old ones from drag racing not the new ones) on the rear p***enger side. Pump it hard for racing and softer for the street.
Could also be too soft in the front . The combination of front and rear roll stiffness [called roll couple ] is what supports the car during body roll. When the front "falls over" it transfers the same degrees of body roll down the ch***is onto the rear springs. Low frequency suspension will also lift in the front excessively during acceleration , so you could have a combination of rearward weight transfer and RH lateral weight transfer. The RR is supporting too much and the LF is almost off the ground.
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