Need spring plate angle calculation

[mnmasotto]

I have a 1987 Carrera with an approximate weight of 2850 lbs. I have 28mm rear torsion bars. I want to raise the rear end up approximately 1". Can someone tell me how many degrees to change the spring plate?

Thanks mark

[uwanna]

The little Tech Spec book for the '87 Carrera says "1 degree change in spring strut inclination= approx. 7 to 9mm in car height" Roughly .25 to .35in. But that's with stock 25mm torsion bars. 28mm bars would definitly make a difference! Go here, real neat calculater.

http://www.rennlight.com/cgi-bin/spring.cgi

[aston@ultrasw.c]

use the link above - whoever put that together is a genius!!

measure your starting conditions and punch the data into the link, this will give you confidence that it works.

[911st]

3 deg's

[Zeke]

Originally Posted by 911st

3 deg's

But, you have to explain the easy way to find 3*. What with something like 24 splines on one end and 28 on the other, it's tricky. It's been so long, I forgot completely.

[911st]

The G50 3.2 rear torsion bars have 46 teeth on the inside of the bar and 47 teeth on the outside.

After getting the car to where the adjustments can be made and mesure the Spring Plate for the starting point.

I would think--

46 teeth on the inside. 360/46=7.83 deg movement with each tooth,

47 teeth on the outside. 360/47=7.66 deg with each tooth.

Thus, one tooth down on the inside and one tooth up on the out side is .17 deg.

3 deg / .17 = 17.65 clicks, thus probably have to turn the torsion bar 17 to 18 teeth or clicks on the inside and outside (bar will go clockwise to raise on the driver side)

Then check the spring plate angle and wright is down (should be plus 3 deg) . Then reset the spring plate to center using the two large bolts near the bushing. Now reset the angle back to the angle written down.

Or something like that.

However, my guess is he already knew that.