pinion angle

62bigwindow · Post by **62bigwindow** » March 12, 2011, 5:40 pm

This may seem like a silly question but,I am getting ready to order a 9" housing and need to know what the pinion angle should be.I am flipping the axle also ,if this changes any thing.Also what angle should the engine be set at.I am putting in a 429/c6.Thanks

Michelle · Post by **Michelle** » March 12, 2011, 10:58 pm

You need a mininum or 1.5 and it is not good to exceed 5 degrees. I always shoot for 1.5 to 3.5 degrees.

cooter · Post by **cooter** » March 12, 2011, 11:13 pm

weld the spring perches in after diff is in truck and you are not guessing on the angle. The less angle the better. As for the motor 2 to 4 degrees is perfect

CTom · Post by **CTom** » March 13, 2011, 11:06 am

You will get many answers to this question. All I can say is how I do it. I always set the pinion at the same angle as the trans tailshaft. I set the motor first by setting the intake manifold/carb mount level(this should be about three or four degrees tilt back). Next set the pinion to the same angle. If I can split the difference I try to set them both at 3*. Works for me.

Gary Seymour · Post by **Gary Seymour** » March 13, 2011, 7:00 pm

I agree with waiting on final pinion angle until your new engine/trans is in place.

I also believe the pinion angle should match the angle of the output shaft/engine crankshaft for the u-joints to stay in phase. (If I am wrong some one chime in).

I set/mounted my new motor/trans in the frame at the same "crankshaft angle" (relative to a flat portion of the front of the frame) that the original 292 was mounted at. Leaving an amount of clearance that I wanted between the bell housing and the firewall tunnel.

Then tweaked the pinion angle last wth shims to match the motor/trans.

Since you have flipped the axle, weld the spring mounts last.

kstones63 · Post by **kstones63** » March 13, 2011, 9:49 pm

I agree with the last two posts. Everything that I have read says that 3-5 degrees is ideal. It should match the angle of the trans. The idea of matching angles is to offset the motion of the other joint. A u-joint that is set without any angle will vibrate and cause problems.
Weld the saddles on after the diff is in the truck and the angle is set.

Kevin

jwh f-100 · Post by **jwh f-100** » March 14, 2011, 7:16 am

I agree with the above, just match the engine with the pinion at 3-5, and just wait until all the weight is added to set the rear.

As Kevin mentioned 0 deg is bad, so I would consider this while setting things up. If you decide on 3 degrees and with the flipped axle you have no agle at the u-joints you may want to go a bit more with the engine and rear to achive a angle at the u-joints. Not to confuse things but if you center your engine the anle needed at the u-joints should be achived because of the ofset rear..

Hawkrod · Post by **Hawkrod** » March 14, 2011, 9:12 am

These guys are right, engine crank centerline angle must be known to set rear angle. The best possible scenario is that all angles cancel each other. This means if the trans is at 3 degrees the pinion should be 3 degrees and also side to side angles should cancel each other. Whatever you do though, never make the driveshaft a straight line from the front of the crank to the back of the pinion gear. The lack of angle will prevent bearing movement and it will eat Ujoints constantly. Hawkrod