adjustable upper rear control arms

[cobraduke]

Originally Posted by Double Venom

John, well done...What a memory!
Center to center of the bolts for mounting the rear end (Lowers is 11-1/4") With adjustable arms this is an excellent place to start and if you're really good you can get a true 4-wheel alignment----AND a correct pinion angle!
DV

Ed,
11 1/4 is center to center on lower arms (fixed) and with adjustable uppers set that dimension on them to start? What pinion angle do you want to shoot for at normal ride height? I believe I read that it should be slightly down relative to the transmission/engine so that when you get on it and the rear twists raising the pinion, it pretty much parallels the trans/engine axis. Is that the goal? My problem with the fixed arms is not vibration, it is wheel hop when I get on it, especially out of a corner, I believe the adjustable upper control arms were developed to allow the Mustang guys to tune this out to help keep the rear planted (especially for drag racing). Is that correct?

Thanks,
Mike