Pinion angle help, please.
Pinion angle help, please. Just wondering if any of you LTx guys can share your specs for setting the pinion angle specifications. I have a Chrome-moly BMR adjustable TQ-arm and I would like to set the pinion angle for street and drag strip (basically a compromise between the two). I don't want an agressive pinion angle that makes the car howl on decel, but I would like to know what is the most you should go for a street car without negatively affecting it's daily manners. I've been told, -1.0 to -1.5 is pretty close to a good compromise on street/track. The car also has a MOSER 12 bolt with 4:11's and T/A girdle and rear Coil-overs (12 way hals), ride height is set to a 2" drop all the way around the car if that makes any difference in your answer. Thanks for any help...
Last edited by 96silverram; Apr 17, 2008 at 02:43 PM.
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I believe I set mine to -2 degrees, but it's been too long for me to remember. BMR Fabrication recommends (-1 to -2) for automatics and [-2 to -3] for manuals.
At any rate -- the idea is that, when you romp on the gas, the rear differential is going to want to rotate, thus lifting up on the frame of the car through the torque arm. This will straighten out the pinion angle at full throttle (towards zero), presumably putting the least amount of stress on the yokes and u-joints. For daily driving, I would adjust it closer to -1, since you'll put more wear on your u-joints just toting around town.
I don't believe it matters what you've done to the car (dropped or otherwise) -- the target angles are the same irrespective of your other suspension modifications.
At any rate -- the idea is that, when you romp on the gas, the rear differential is going to want to rotate, thus lifting up on the frame of the car through the torque arm. This will straighten out the pinion angle at full throttle (towards zero), presumably putting the least amount of stress on the yokes and u-joints. For daily driving, I would adjust it closer to -1, since you'll put more wear on your u-joints just toting around town.
I don't believe it matters what you've done to the car (dropped or otherwise) -- the target angles are the same irrespective of your other suspension modifications.
If you run no more than -2 degrees for a street/strip car, I'm pretty sure your safe. I run about one and a half degrees negative. If your car is lowered, there's a good chance the angle is way off. You gotta love an adjustable torque arm and the anti squat it creates. It really plants the tires.
