Working out roll-centre on semi-trailing arms.

[Boyracer]

OK so I know how to work out my roll-centre on my front suspension (simple McPherson strut) but I'm lost when it comes to an E30's semi-trailing arm at the rear.



Also, what happens if my mass axis and roll axis are dropping towards the back of the car but the lines are divergent? What little I know doesn't cover this, I know divergent lines mean oversteer but I've also heard that lines that drop towards the back of the car mean understeer. Man, I wish I was still running on stock suspension now.



If anyone is any good at telling where an E30s roll centre is by eye this is how low my car sits now. Too low for me but when you're using secondhand parts you have to take what you can get. If it makes any difference when I drift I move to 205/50-60 R15s on the back, still running 195/50 R16s up front.

[Piner]

This question would probably be better asked on http://forums.bimmerforums.com/forum...play.php?f=293 since few people on this forum (besides the FD guys) even know what roll center is.