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I am setting up my engine setback, I have already cut the firewall for bellhousing and head clearance.
I am waiting on my motor mounts, and when I get that set I will order a tranny crossmember, but I still haven't mounted my replacement rearend or my front axle, but the stance of the car is fairly close to what it should be when finished.
I was wondering if I can still set my pinion angle or crankshaft angle before fitting the new rearend and straight axle? And what do I set it at? I have leveled the carb flange before and set some up that way and no driveline problems.
Any advice would be greatly appreciated,
Thanks Andy
 

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I never set pinion angle before putting a rearend under a car. It's so much easier to put the perch, axle, and U bolts together in the car, and then get it centered first. I loosely install it with the pinion pointed slightly down, and then put my angle finder on the pinion and use a floor jack to jack it up into position. Once it's in position I tack the perches and check my angle again. When it checks out good, I permanently weld the perches and tighten down the U bolts. It's nice to not only have the weight on the suspension, but also the tires on the ground, even if you need to put blocks under each tire to be able to crawl under and set the angle or tack the perches. Of course you need the car on a fairly level surface, and if you jack it up, it needs to be done equally front and rear to accurately set the angle.
If you don't have a driveline you can use a long straight edge to simulate it's position, and check driveline angle between the pinion and the tailshaft.
With the Austin's ladder bar-coilover suspension I mocked it all up under the car and set the pinion angle with it in place. Then I tack welded the ladder bar brackets, shocks, front ladder bar mounts, all to the car. Checked it all again, and then pulled the rearend back out of the car to weld all the pieces on the rear axle. Then welded up all the pieces in the car and put the rearend back under. After that I did final adjustments with my heim ends. I had the Austin rearend pretty flat at first, and I had some vibration at freeway speeds, especially on deceleration. I knew right away it was pinion angle, so I cranked in a couple degrees up and it all went away.
One thing to be careful of is not to get too much up angle on the pinion, especially with leaf spring setup. As the rear travels up the driveline angle flattens out, so you want the angle to be flat enough to keep the pinion pointed at the tailshaft of the tranny. But you don't want the pinion pointing down ever, unless you had some weird situation where the rearend was higher in the chassis than the trans. Most guys will stay about 3 degrees up, but that's not a set amount, as the greater the difference in rearend to trans height, the more up angle you can have. And the travel will also affect the angle setting. Vehicles like 4x4's need a lot of pinion up angle with the extreme differences in rearend to trans.
If by chance you're setting up a leaf spring rear and you don't quite get perfect angles, or you need to adjust later; they make wedges that can be put between the perches and springs to correct angles. They're cheap, and come in anything from 1 degree to 5-6 degrees.
Hope this makes some sense or helps.
 
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