Welcome! Solid cars for some fun.
Moosehead control arm bushings. We spent a number of races chasing a violent brake shake (unless you were really on the brakes) and that seemed to fix it. Sometimes a new rubber bushing would fix it for the day, but not always.
You'll get little life out of your fuel tank and pumps unless you do something about its starvation in right hand corners. We get 7-8 gallons in before it is a problem. I'm going fuel cell this round, but just saw Ireland Engineering's solution that sounds worthy.
Because of above, my exhaust needs to be re-routed (if you're interested). That was worth about 25lb savings from the stock setup, and a V-band clamp makes dropping it super easy. I'm in TX...
Just added e34 540i rear brakes and a brake bias valve and it helped out a good amount with wear. The ABS unit developed a clog to the RR and I didn't want to deal with it. We still have the stockers up front with solid bushings and good pads. Make sure they see air. The brakes, with Hydroboost, work really well.
Plain Jane '86 BMW 535i - Current
RIP People's Elbowed Protege - 2010