Is anyone using the ATI super damper on a big block with the big block chevy hub? That is what my set up is and I am looking for advice on a crank trigger and mandrel for a vacuum pump. I have an Aerospace vacuum pump and got the BBC mandrel but the inside of the mandrel is not machined for the front bolt and washer. Wondering if anyone else has ran into this issue.
Thanks!

You have to have a machine shop put a pocket on the inside of the mandrel for the crank bolt and washer.

The is the Aerospace Components mandrel for the BB Mopar. It shows the "pocket" to clear the large Chrysler bolt and washer.

Thanks Andy! I was wondering if that was the route I was headed. Thanks Jim for the picture showing what is done. I will get this done.

Back in the old days I used to build my own Mopar spline drives just because there wasn't anything on the market that fit a BB Mopar. Then I switched to buying the ATI damper with the BBC bolt pattern and using a Peterson BBC blank. The Peterson blank still has to be relieved, but it is less work than starting from scratch.

Same here. My old ATI damper has the Mopar 6 bolt pattern. Wasn't much available for Mopar back then. I made most of my FEAD out of many left over pieces from other Ford and Chevrolet builds laying around and came up with this.

Yep, the "old days". ATI damper with Chevy accessory bolt pattern. Not much made crank trigger and pulley wise for Mopar then. Easier to make brackets for the pickup etc, than to reinvent the wheel.

No reason not to do something to use the most common accessories available now either.

Andy, I like that big nut on the end. Should be suitable for turning the engine with a wrench by hand.

Yes, the spline drive setup from Peterson is strong enough that the engine can be rotated with the large nut. The Chevy style mandrels will break if you try to use the center bolt to rotate the engine.

Yea, it is my understanding that the center bolt on those is just to clamp the pullies/spacers together; not to turn the engine to TDC etc. Especially with spark plugs installed !
Do you think the other aluminum mandrels would be OK to turn the engine by hand if one of the spacers was replaced with a big wrench hex with a keyway to the mandrel center? (or like some pulleys have a set screw with sized end to engage the keyway). For example a 1" dia mandrel with a 1-1/2" hex; or a 1.5" dia mandrel with a 2" hex.

Maybe, I guess I'd try it and see how it felt. The keyway should be strong enough to withstand the load and so should the 3 bolts for a Chevy pattern or 6 bolts for a Mopar pattern. With spark plugs installed it can take over 100 ft-lbs to rotate the engine, maybe more on a igh compression engine.

I made a custom drive for a friends engine. I machined a square drive in to the front, so he could turn the engine over easily. Not sure if I have a pic for it, if I find one I will post it.

I installed a thread insert that dropped the 3/4 diameter thread (minus the locks) down to 9/16 thread. I then used an ARP washer and a a socket head flat screw. The top of the screw sits flush with the washer, which is tapered, and easily cleared the mandrel.

Different brand of dampner and mandrel so your results may vary.