Only my second year running this car but I'm getting a bit of body roll. Car wants to squat/ roll to the right at launch. Can I stiffen the passenger side shock to help fight this? Could be leaf spring?
Suspension is 112 rate multi leaf, caltracs and Calvert 9 way in the rear.
Front is cheap 90/10 and trick springs.
Any help is much appreciated.
My 68 also has a tendency to pull right when caltracs are set to neutral position. You might want to tighten the right side caltrac bar and see if that helps. About 1/2 turn took care of the issue for me.
On initial setup the caltracs were just barely touching on the driverside and half turn preload on passenger and it pulled to the left. I added a half turn to the driverside and it launches strait.
My front end is shit. The springs have so much sag and it comes up too fast it's unloading the rear.
A buddy has some coilovers I can use. See if that helps with the unloading.
6pt bar, frames are tied I have new body bushings, just never got around to putting them in yet.
I tightened up the passenger side rear, won't be able to test it till the weekend.
Two things at work here:
1) The torque input to the rearend is causing the rearend to pivot about the center; the drivers side headed down and passenger side upwards. You can easily calculate the potential loading added to driver tire:
= (Horizontal ground force) / (rearend axel ratio) x (loaded wheel radius) / (trackwidth of rear)
2) the second part is the vehicle body reaction in the opposite rotational direction which is stopped by two points (front and rear passenger side tires). Here the ratio of vehicle suspension roll resistance comes in.
example: if the front end was very stiff compared to the rear then you will maximize the rearend loading difference; the drivers side gets +296lbs and the passenger side gets -296lbs. Depending on the starting static weights the car would yaw away from the side with more loading.
if the rear suspension was stiff when compared to the front then the rear suspension would transfer this load right back on the passenger side axel housing for a net zero load difference in the rear.
the initial +296/-296 from axel tilt would get its opposite reaction added by the body suspension for a -296/+296.
This is the purpose of the rear anti roll bar is to stiffen the roll resistance of the rear compared to the front end.
If you had an equally stiff front ARB then you would reduce the effect and end up with +147/-147 at the rear. The front end would see a -147/+147 (hence the front driverside lifts higher)
Update:
Put a sway bar in because I'm lazy and didn't want to fab up an ARB (maybe this winter). Passenger shock is one click tighter than driverside. 1/4 turn total preload on caltracs, both sides. Front 3 way shocks are on middle setting.
Was able to knock off a tenth on the '60. Launches strait. Happy with that so far.
Yea. Was doing some hard tire testing. Half second slower than last year. Using cheap tires.
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