get one off a full size van has the snapring cover on side.

Pinion Angle
Tired of breaking cases and drive shafts? There are many books that misled you on setting the pinion angle. For Drag Racing this is simple. You are trying to set the pinion angle to be parallel with the centerline of the engine & transmission on hard acceleration. To achieve this you must first figure out the parallel setting of the rear end to correspond to the angle of the engine & transmission, then add the proper amount of pinion angle. Add 1 deg. for 4-Link vehicles, 2 to 3 deg. for ladder-bar vehicles. Place stands under suspension to duplicate vehicle at ride height. Caution do not remove drive shaft without securing vehicle first. Take measurement with drive shaft removed.

I checked the pinion angle relative to the tranny mainshaft centerline when I first broke it.

Hmm, this looks less than ideal. Jackstands under rear axle.

I think thats ok.
The shaft ends at the seal boot and you want 1" of room so it does not bottom out in yoke.

I wouldn't want the shaft any shorter than that, mine the boot is about a 1/4 inch away from the very beginning of the radius, from the point you are showing how far will the yoke slip into the housing till it bottom's out?

Got a chance to play in the garage today. Unbolted the shaft and drove it all the way in.

Looks like I am 1.5" from bottomed out.

The shaft is definately going in to check balance, think I should lengthen it .5-.75" while I'm there?

how will they LENGTHEN it ???

it looks to me like it is sticking out too far though

Something you may want to consider doing, since the car is up on jack stands.

Measure the angles:

-Get car as level as you can supported by suspension
-Use a plumb bob and masking tape on the floor to find the centerline of the CAR
-Now find the centerline of the Crankshaft / Transmission shafts. Use a plumb bob off the front pulley and off the trans yoke. Very easy to find where the engine / trans is POINTED relative to the CAR.
-Now find where the rear end is pointed. You can do this with a laser level on the rear axles / wheels,.....
-Everything should be lined up and parrallel to the car centerline.

If you have the rear pointed to the right and the engine / trans pointed to the left,....then you drive shaft is going to be at a crazy angle and want to swing like a hammock.....this can break stuff!!!!!!

I just went through this when setting up my Dana. I've got it all spot on!!!!!!

Let me wake this thread from the dead now that I got the rebuilt tranny/engine back in the car.

First off, the 2" measurement above is actually a little bit more. Maybe 2-1/8th. Its 2" when it was broken and must have had a gap.

Secondly, I verified the output shaft is straight on v blocks.

Third, I did find a truck tail and its very beefy but I still think I have a bad situation going on.

One thing that was really eating at me was why did I make a shaft that short?? I'm not that dumb, I wouldn't have ordered it like that. And why did it end up to be the OE length for my application but still be that far out??

One thing popped in my head. When I first ordered it I had an A body A833 in the car and now it has a 904. While the OAL of a 4 speed and a 904 is practically the same, I did have to buy a new slip yoke for the smaller 904 output.

Perhaps the aftermarket yoke is different than others???

Probably too late

New shaft on its way. Should yeild 3/4-1" of pullout when all set.

I guess the stackup of differences of the 904 vs A833 coupled with the change in 29 to 26 spline yokes, plus swapping a stock mopar 7260 pinion yoke for a 1330 spicer yoke just didn't work in my favor.

I called mark williams after my new shaft came in. It has a 1.125 of room till it bottoms out. I thought it was a bit short. They said they like 3/4 to 1" on race cars. I was told not to sweat the extra 1/8th.
I know that they make different length pinion yokes so make sure you use all the parts that will be in place when racing.