Thread: Lowered rear/Drive shaft angle

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I'm getting ready to mount the rear axle in my chassis. I'm running a transverse 'T' style spring with a Ford 8" with radius rods.

Due to the 10" kick and 4" underslung mounting on the axle, the pinion ends up above the tail shaft on the tranny.

I understand the basic geometery of parallel tail shaft & pinion with 6 deg. of angle trough the drive shaft.

My question is: With the tranny (with 6 deg.'s +- built in) below parallel and the pinion above parallel, what do I need do to acheive the proper line through the drive shaft? none of the brackets are on the axle yet so I can rotate it anywhere it needs to be.

Thanks,
Marty

can you raise the output shaft of the trans any??? How long will the shaft be???

Doesn't matter. Just have the tranny pointing down ~3 degrees and the rear pointing up ~3 degrees.

Currently the drive shaft length is about 15", I may be moving the engine forward, so I could gain another 2-3". I can raise the output some, but I need to watch the carb level if I go too far. With the carb level, I have about 5 deg. drop at the output shaft now.

you can correct the level of the carb with a manifold change or adapter plate or milling---the driveline angle is of primary importance

Thanks Jerry, but the intake change is a no-go. The engine I'm running has an integral one piece head/intake! Dont' Ask. I wanted to do something different this time and I went a little too far out of the box. I could have a carb to intake spacer made to accommodate the angle since I'll need to change that anyway.

I'm beginning to think I might be over engineering this drive line problem. It's one of those things that at first looked way worse than it might actually be. I was a little thrown off by the fact that the axle pinion was above the tail shaft instead of below like usual, but the more I think about it, I'm not sure it's such a big deal.

I really appreciate the input, it's given me some different ways to approach the issue.

Marty

Here's a link to a pretty good artical on Pinion angle. http://www.buickperformance.com/Pinion.htm

Bill Currie also mentions in his writings and in his recomendations when you purchase a rear end from "Currie" that most single u-Joints have a working deflction of 3 degrees and they always strive for no more than 2 degrees. It's good solid advice I think but a little common sense is good as well.

RS

I don't understand what you are trying to say about the 10 inch kick and 4 inch underslung causing the pinion to be above the trans output shaft----the pinion will be located from the ground and diameter of your wheels--it has nothing to do with frame kick or how its mounted--the ford 8 and 9 inch rears have probably the lowest pinion of about any rear except for a quick change lower shaft. Your problem is from the engine trans mounting angle and thats what you need to correct---especially with a short drive shaft

Don't worry about tilting the carb forward. It'll still work.