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jpnovak jpnovak is online now
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Join Date: Apr 2000
Location: Austin, TX
Posts: 7,135
suspension refresh, ride height and Corner Balance

I have just recently updated the suspension on a friends 78 930. He is a member here and may chime in. The updates include reinforcements to the spring plate bosses, ER poly-Bronze bushings on 4 corners, 22/31 torsion bars with matched revalved Bilsteins, new sway bar bushings, alignment and CB.

So, I have some interesting numbers when the car is setup. All the numbers below are with a 195# driver (me) in the seat.

First, setup. Car sits dead level R/L with 25.25" rear ride height. Front is 1/2" higher.

FL FR
519 541
RL RR
802 858
cross weight 50.6%

The problem with this setup is preferential bias across the front wheels and lots of weight difference between rear weights. RR is heavy for my tastes.

Improved setup.

FL FR
526 530
RL RR
866 869
cross weight 50.01%

This is where I ended up. The car is dead square from a suspension setup standpoint. The car drives amazing here. Perfectly poised - It just looks a little funny. The challenge is ride height is now 1/2" higher on Driver's side. With stiff torsion bars, the car does not sag enough to level when sitting in the seat.

Generally, my procedure is to set the front height level and the same height with the same weights to balance front wheel loads under braking. Then I adjust rear loads up/down until they are close. I typically target 0.2% difference L to R diagonals.

I am just not sure about the first numbers where there is so much extra weight on the RR wheel.

Which would you choose and why? Lets hear from you guys. I know some of you will say that for a backroad street car the first setup is good enough. I don't usually do good enough.
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Old 02-04-2014, 07:31 AM
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