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Thanks for all the input guys. So what I am hearing is that as long as the engine/trans angle is opposite of the pinion angle, I am good and dont concern myself what the driveshaft is doing, correct?
So in my scenario with a street driven vehehicle with 700 HP, on a level floor, the trans is down 4* so the pinion should be up 2* allowing for a few more degrees further up rotation while under load?
Thanks!



Part of the confusion of pinion angle settings is that you are trying to take an educated guess at how much the pinion angle will change under load. The generally accepted change for leaf spring cars is 3-5* for auto cars and 5-7* for sticks. Obviously a high H/P car with soft springs will wrap the springs up more than a low H/P car with stiff springs, and a car with clamped front segments and/or slapper bars, Cal Tracs, etc may be only 1-2* deflection. And here's the rub - there's also u-joint operating angle to consider. And while on paper your car, with the trans pointing down 4*, you should need the pinion at 0*, so your leafs can let the pinion rotate 4* up to make the math for pinion angle work - that may leave your u-joints with no operating angle, (the engine/trans/driveshaft/pinion are all in line)and prone to fail from brinelling. That's why I mentioned that sometimes you have to change the engine centerline to correct the pinion angle. I'm sure there will be some that disagree, and this subject has been beat to death in the race forum. It may take several adjustments to get the whole package where you want it.

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