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dfhotlm33c
07-18-2011, 06:41 AM
This is an 02 Boss, supposedly a Mastersbilt copy. Set ride heights/scaled car, etc yesterday.

LF recommended ride height from Masters is 2 7/8" (Bottom of frame rail to top of lower control arm)
RF is 3 1/8"

When at these heights, the upper arms do not have a significant amount of angle to them..RF is about 12*(8.5" length upper, mounted outside), and LF only 4* or so. (LF upper is a 10.5", mounted inside frame.)

I recall reading in an older book (Duke Southard's book on chassis setup from 20 years ago, if you are familiar) that you want somewhat more angle in the uppers than this. Is that just old knowledge, or is this setup wrong?

At this ride height, the lowers are nearly parallel to ground, which I was told along the way is what you want. In addition, the shocks are each extended about 4-5", which gives us the recommended amount for 4" of wheel travel with no problem. Also, at this ride height, the camber settings are exactly at Masters recommendations (LF +2*, RF -4*)

Just want to make sure these ride heights are a good starting point.

hpmaster
07-18-2011, 07:28 AM
The only way to check for sure is to either use a roll center frt end geomitry computer program or do a layout actual size on butcher paper. What most people shoot for is a roll center between 2" and 4.5" off the ground. I have found the upper control arms can be quite flat, little angle, when you are in that roll center range. But the only way to know for sure is to check it.

dualdj1
07-18-2011, 09:18 AM
my suspension tracker has a front roll center calculator in it:

http://www.4m.net/showthread.php?212276-Suspension-Setup-Tracking-Software