So I'm getting ready to install the 390 stroker, but have a concern about the damper. The crankshasft only has 1.5 inches of shaft to install the damper on, but the damper mounting tube is 2.5 inches deep. This will leave about 1 inch without any thing to hold on to. Is this normal?

 

I would call the manufacturer, and have a chat with 'em. Isn't that going to push the crank pulley out too far as well?

 

I could be wrong, but I was under the impression that Fluidampr didn't make dampers for small block Magnums.

 

Sorry, bad use of descriptive terms. The harmonic balancer is a Napa factory replacement.

 

Are you saying that there is only an inch and a half of crank snout coming out past the timing chain cover?

 

Compare it to your old one, and see what you think.

 

From the timing chain sprocket.

 

That does seem short. I think the OEM crank is 3-4 inches roughly but it's been a couple years since I put my timing chain in.

 

Timing chain and crank snout with bolt.
I know it's a big picture, but you need something with some detail.

The balancer should go through the front cover onto the snout with a round section, leaving the balancer portion and pulley in the right place. Note the keyway, and how far back it goes.

 

This answers the question. Just pulled the balancer bolt of an untouched 5.2. The crankshaft does not go to the edge of the balancer.