driveshaft yoke engagement

[flyinlow]

how much do you need?

[John_Kunkel]

With the weight of the car on the rear wheels, 3 3/4" from the end of the tailhousing to the center of the u-joint is correct.

[flyinlow]

Thanks John,  Looks like it is a little short on engagement. My sons car, 1970,it came with a 4:10 . We swapped a 3.23 in to it until he gets his 518 done. That will be awhile. Was a 318 car and looks like they used the small driveshaft with 7260 Joints. I guess a new driveshaft will be added to his list.
If the correct 3 3/4 in. is set do you know how much spline engagement there is?

[firefighter3931]

Spline engagement depends on the length of the factory yoke. From my experience the factory yokes are longer than their aftemarket counterparts. 

I set mine up with 1.5in of travel before the yoke bottoms out in the case. This allows for suspension travel. If the driveshaft is too long the yoke can bottom out and break the tailshaft.


Ron

[John_Kunkel]

The original factory rear seal with the dust boot will only work with the 3 3/4" dimension or close to it; if you have a seal without a boot the old "bottom it out and pull it out one-inch" will work (again, depending on the yoke).