(quote old thread mattyn)
QUOTE (sr_rolla @ Nov 19 2008, 05:14 AM) *
the theory is that because the upper and lower arms are at different lengths the diff will try to twist itself as the left and right ends move in different directions (ie: the left moves up and forward while the right trys to move back and down). When u convert the rear end to more solid bushings the diff can no longer pivot in its bushes so the car has a tendency to lift wheels and push understeer. If u drill out the upper bush as u described the diff can pivot as it is meant to do.
What i would suggest doing is trying the drilled out upper arm 1st and if u feel its a problem later on, get some new bushes.
so i guess the question now would be WHO ELSE RUNS A POLY URETHANE BUSHED REAR END??? and what have you found...?
im under the impression that Poly urethane bushes still have some give.. wouldn't the rotational/pivot issues only really come about with a rose jointed un-equal length setup? ie no movement??