383 Harmonic balancer question

Excellent. Can you get a good picture of the crankshaft and post it? We can confirm cast or forged.


Just noticed the flex plate is indexed meaning it only bolts on one way. I wonder why that is if it’s neutral balanced?
The balance internal or external is not achieved with the flex plate. Just the converter or flywheel and balancer. That appears to be a steel crank, but if you can turn a rod throw straight up so we can see the parting line, we can confirm it.
Thank you so much for all the help guys. I think I will try a new damper and take it from there. The engine won't be back in the car for a month or so
If it’s a cast 383 crank it will still take a neutral balancer. Kim
Really? Now that's something I was not aware of. Thanks. It appears to be forged, though.
Yes it us forged. I have has a few 383s with the drilled damper from factory. Kim
So then they are like the 318 then. Cast or forged, still internal balanced. Good to know. Thank you drive through.
Just for the fun of it.

Make up a tubing shaft 18" long to fit the ID of whatever balancer you want to check for neutral balance. Find a way to chuck the shaft up in your 500 rpm 1/2" drill.

Install a Pillow Block bearing in the ceter of the shaft and clamp the pillow block housing in the vice.

Slide the snug fit balancer over the end of the shaft 6" and spin it up with the drill.

You will know right away if it is balanced or not.

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