in the rear, there are metal dogbone links that connect the spindle to the subframe, did you rebuild or replace any of those? how do they look?
can you define "twitchy"? say, there is a lane with construction and as you cross the road grooves, the car tries to follow them? or are you saying when the road pitches to the outside or on a curve the car tries to shift down the slope? or is it all of a sudden the car just launches one way or the other with no reasoning behind it?

50PSI on an automotive road tire? really? I'd start with fresh soft compound tires and see how it feels from there.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!