I'm in over my head here. I know of a six pack damper for sale. I don't know if I should buy it or aftermarket. I'm not concerned about the way the damper looks.

I want to build a 440 block that I have. It's standard bore with no wear. I have a forged 440 crank that I assume will need to be turned down ten thousandths. I've also got a set of origianl six pack rods and pistons with extremely low mileage.

Do I need the six pack damper or can I go with aftermarket. I'm planning on taking all the parts to a machine shop to get it balanced.

With the stock (very heavy) rods and pistons the original balancer may be your best bet. If you use it make sure to take it to the machine shop that balances the setup.

If you went with lighter rods and/or pistons it would balance easily with an aftermarket neutral balancer. This route would let you use a fresh balancer and reduce reciprocating weight and stress in the bottom end... a much better solution.

The six pack/six barrel rods were super heavy and add to the complexity of engine balance when a bunch of non original parts are pulled together.
The standard 440 rods (LY I think) are the default better bet. less reciprocating weight, faster revving and less stress on the crank.

Thanks for the replies. It sounds like I would be better off scrapping the rods.

But, I want to use the six pack rods. I was wondering if I need the six pack damper, or if there are aftermarket dampers that would do the same thing.

I think I'll talk to the machine shop that will do the balancing. I'll also contact some manufacturers of balancers.

Again, I appreciate the responses and I may decide that it's best not to reuse the rods.

If I recall, all 440 HP engines used the same rods, regardless whether it was a 6-bbl. Only '69-1/2" 6-bbl rods were heavier than for the 4-bbl.

the profesianal products sfi race dampner is a three in one. It comes with two bolt on weights you use no weights for internal balance a certain weight for the six pack and both weights for externaly balanced

1969 440 rods were all the same "LY" forging. ( 350hp - 375hp - 390hp ) The balancer was "neutral".

1970 saw the introduction of the "Six Pack" - heavy rod. Used to slow the reciprocating assembly down. (& increase its warranty life)
The "LY" rod & balancer was still used on the 350hp engine. The offset weight balancer & "Six Pack" rods were used on the HP engines ( 375hp - 390hp )