I have a new in the wrapper arp oil pump stud.

Do I need it?

Is the stock bolt adequate?

How do I install the stud?

Hand tight: and then torque the nut to 65 ft lbs?

Also related...

How much travel do I need in the oil pump drive shaft with the dist installed. I do not want it to bind, but I don't want it to disconnect either.

I have a dist with a collar and can adjust the depth.

 

Note that the hole in the main cap for that bolt, goes ALL THE WAY THROUGH, to the back of the bearing. If you put the stud in too far or use too long of a bolt, it will press on the back of the bearing insert and cause a failure.

Yes, something in the 55-65 range would be appropriate for that nut, like most any 7/16" hardware, since torque goes with hardware size. As always, the engineers who designed the system chose a size of hardware adequate to give the required clamping force when torqued to its "nominal" kind of torque. Had they needed more or less clamping force, they would have chosen a different size fastener, which would then also have brought its own "nominal" torque value with it.

 

The stud has an allen drive on the top right? IIRC you tighten it until the threads bottom out. I'd use red loctite as well, and just snug it into the bearing cap, 20 ftlbs maybe. Let that setup. Then install the oil pump and torque the nut to 65ft lbs as mentioned.

Adjustable depth? huh, no idea on that one.

 

No; that's just it. You DO NOT do that.

The stud will "bottom out" ON THE BACK OF THE MAIN BEARING. Very very very very very bad. And not good, either.

 

Ok! Fair enough then.
With other studs, head studs, main caps etc, is that what you'd do? Tighten until the end of the stud threads hit the surface?

So i'd guess you'd want to remove the #5 cap and put the stud in and watch how far in it's going? I would have thought the stud should be the right length such that it'd bottom out on the threads before the end of the threads hit the main bearing.... Seems like a bit of a design flaw eh?

 

Yup, with other studs, that's about it.

I'm not sure if the ARP oil pump one is made the same way. It'd be something you'd definitely want to check with the main cap off the motor, BEFORE porking the pooch, though.

You'll also note that the main cap has different thicknesses for the 3 journal sizes of small blocks; and that the surface in the cap that the stud WOULD bottom against, is left "as-cast", a little bowl in fact, NOT machined flat. So it has LOTS of tolerance. There's clearly ALOT of ways that "bottoming" that stud could create problems.