In the live and learn category, I had my stock length BMR uppers pulled off and my old upper CAs bolted back in place. 80-90% of my wheel hop on turning while accelerating from a stop is now GONE!! It's SO nice not to have that constant shuddering when launching. As I expected, it's quieter, too.
The BMR bushings at the diff had their edges torn, no doubt from the twisting action of the steel yoke when one side of the car jounced and the other didn't. One of the arms had the sleeve in the black plastic bushing at the frame end shifted to one side, permanently deformed. I'm a definite believer in the Global West assertion that the uppers MUST be able to twist when one side of the axle compresses and the other doesn't. It only cost me $380 (arms + two installs) to learn this lesson. [img]graemlins/
I don't doubt rigid upper arms are fine for drag racing applications, but given the geometry of the 4 link design of our rears they are unsuited for track work or street driving unless a different, more compliant bushing can be designed. But at that point, what's the advantage over stock uppers? The alternative would be an upper split in cross section half way along its length with a real stout joint that permits rotation of the two sections but no axial movement. Probably too rich for my blood.
My old uppers, BTW, were in great shape after being on the car over 100k miles. No cracks in the metal or rubber, and no oblong holes, just a little surface rust.
I guess to have only one truely bad experience in over 9 years of modding is still a pretty good record.
If anyone wants two slightly used stock length BMR uppers, make me an offer. [img]tongue.gif[/img]