Does anyone know the gm part number for
A flywheel for a 454 1 pc rear main, 168 tooth, for
Internal balance crank.

Seems to be a lot of confusion on this subject.

Thanks to all

Don't think one was ever made for a one piece seal 454. They do have internal balanced type flywheel on a 572 crate engine. The thing in question would be if your coupler would bolt to it beings they use a 11 1/2" clutch compare to 11". #12582964 is the part number.
http://www.jrgmparts.com/GM_Performa...gm_chevy_.html

There are aluminum ones, not GM which are drilled to work with several different size clutches. Not cheap and don't if you would want an aluminum one anyway.
http://www.ebay.com/itm/McLEOD-ALUMI...-/110890974968

A stock 454 wouldn't be internal balance, not saying it couldn't have been internally balanced at a machine shop. If it truly is internal balance then the 168 tooth flywheel off of a 427 should work.

427's were Mark IV's.........2 piece seal.

one flywheel fits both one and two piecr seals and you will need to use a 427 (like mentioned) harmonic ballancer and flywheel...

I just bought one from Summit racing. like $200

After fooling with 454's for decades I would never swap flywheels with any other motor with out taking it and the balancer to a shop to be balanced.
How come your motor is internally balanced?

I have a 454 1pc seal block. mark v
I need to buy another crankshaft and decided to go with a 4.25 stroke because I already have correct rods/pistons.
I also need flywheel and HB.

I noticed that internal bal stroker cranks are much more abundant.
I figured it would be easiest to go all neutral.

Guess I was wrong?????

I think the internal balance is better, just use the neutral balance 427 flywheel and hb. Summit, Jeg's , GM all sell them.

I just had the same deal when I stroked my GEN VI to a 489, I took my OEM factory flywheel, ground out most of the counter weights and then took it to the machine shop and for $40.00 had it nueral balanced. Done Deal. Just my 2 cents

Make sure you get a new harmonic balancer to match. Don't use your old one, it was for an externally balanced set up