Did a FH V8 sit level in the frame, fore and aft?
 

I'm setting up a 9 inch rear in my 28 roadster pick up. What angle should I use for the universal?

When I get the V8 block back from the machine shop, I should be able to match the angle.

Did these vintage V8s sit level?

I need to get it on wheels. Can you help?

Thank you, Bob in Council Bluffs, Iowa

Re: Did a FH V8 sit level in the frame, fore and aft?
 

As engine/Transmission assemblies may have clearance issues requiring angle adjustments, wouldn't be easier to determine final angle before setting the diff?

Re: Did a FH V8 sit level in the frame, fore and aft?
 

Some articles state 1 1/2 degrees and others say 2 to 3 degrees for a 9-inch or just about any modern type rearend. That means the u-joint is angled down 1 1/2 degrees coming out of the trans and then at the other end it should angle upward the same amount, 1 1/2 degrees. Figuring with a load on it driving, it will straighten out to just about zero, the bouncing up and down will cause enough movement to keep the needle bearings lubricated. You don't really want the angle set at zero degrees, because the needle bearings won't rotate in the grease and get lubricated, that why maybe 2 to 3 degrees might be better.

A flathead engine does not have much room to drop in the back before the intake hits the firewall if you're trying to straighten out the u-joints. Besides, I would think you want the intake sitting level, so the float bowls are level. It also depends on the length of the driveshaft. Look at some of the lifted jeeps with short driveshafts, they do terrible things to the angles of their u-joints. They'll work but for how long? You might not have the room (too short) to get the angle where it should be, you'll just have to get it as close as you can. Set the engine and trans in the pickup and load it up with some weight so it would be like it would be finished. Stick the rearend under it and see what you'll have for u-joint angles.

Re: Did a FH V8 sit level in the frame, fore and aft?
 

Make sure the U-joints are phased correctly.

https://www.beldenuniversal.com/inst...-joint-phasing

Re: Did a FH V8 sit level in the frame, fore and aft?
 

Yes, vintage torque tube Ford V8s sat level in the chassis. When Ford cars switched to open drive lines in '49, the engines/transmissions sat lower in the rear to properly line up with the new hypoid differentials, and the reason early intake carb mounts are level while '49-up carbs are angled to the front.
I strongly suggest you get the chassis (frame/engine/axles) at ride height before you try and set the rear axle for correct pinion angle. Ideal U-joint working angles are matched 1 to 3 degrees.

Re: Did a FH V8 sit level in the frame, fore and aft?
 

Dana has calculators and design guides to help you though the design process.

https://www.danaaftermarket.com/calc...Calculator/202

https://www.dana.com/globalassets/re...guidelines.pdf

A digital level is best to use, I have one similar to this:
https://www.homedepot.com/p/Swanson-...E&gclsrc=aw.ds

And remember you can always measure surfaces 90 degrees to the crankshaft center line (front or rear face of block) and do the math.

Re: Did a FH V8 sit level in the frame, fore and aft?
 

My experience led me to believe that WITH A TORQUE TUBE, the centerline through the crank shaft, transmission and torque tube should one continuous axis at about 3º. This will reduce wear on the U joint and have rear end lube drain back to the differential. (The transmission mounting surface on a '32 K member leans back that 3º.)

WITH AN OPEN DRIVE SHAFT, the crankshaft / transmission centerline can be pretty much anything and the pinion center MUST BE PARALLEL to the trans. But, they must be off set to provide a 5º or so (some one check me on the number) so that there is a constant rolling of the roller bearings in the U joints.

This all my humble opinion.

Re: Did a FH V8 sit level in the frame, fore and aft?
 

I have swapped out many diferrent rear axels over the years and have for the most part (except on high lifted trucks) always put the pinion on the the same plane as the crank and tail shafts. In other words if they were the same height they would line up but they are not so they don't. Acording to my old drive shaft guy you want a minimum of 3 degrees bend at the Ujionts and if the line is straight, tip the pinion down to get this amount of bend. This would occur sometimes when we lowered a car or truck. It's funny thinking back, he never said what the max was you could bend a Ujoint that I can remember. The bend cancels out viberation and lubes the Ujoint. Tim