440 Internal or External Balanced

[Chukar]

Buy a $20 bore scope camera off Amazon an look thru the oil pan drain plug hole. Cast crank; thin parting line, square edges on the counter weights. Forged crank; rough 3/8” wide parting line, rounded edges on the counter weights.
Doug

 

[Chukar]

Nice! Great idea. Thanks

 

[Chukar]

Nice Great idea. Thanks

 

[Chukar]

Absolutely Wrong!!! A 66-69 440 including the 69 440-6 are all originally internally balanced....

A 70-72 440-4 along with 70-71 440-6 engines are externally balanced but it is a fairly small balance weight on the damper & flywheel/torque convertor... They run a forged crank but they also run heavy rods

73 & up cast crank 440's are all externally balanced with a big weight on the damper & flywheel/torque convertor....

So the bolt pattern keeps a forged dampener from being installed on a cast crank and vise versa....?

 

[Chukar]

Buy a $20 bore scope camera off Amazon an look thru the oil pan drain plug hole. Cast crank; thin parting line, square edges on the counter weights. Forged crank; rough 3/8” wide parting line, rounded edges on the counter weights.
Doug

Great idea thanks

 

[1 Wild R/T]

So the bolt pattern keeps a forged dampener from being installed on a cast crank and vise versa....?

Nope, you can swap parts but the balance will be wrong..
The crank pulley bolt pattern was changed in 72 from having a single bolt offset about 1/8" to symmetrical...

 

[Chukar]

basically - if it has a thin balancer it is internally balanced... the thicker balancer with a slight taper is externally balanced

OK. Can the balancers be installed to the wrong crank?

 

[BSB67]

So the bolt pattern keeps a forged dampener from being installed on a cast crank and vise versa....?

Triple nope. I just don't understand any discussion about a pulley bolt pattern as it has nothing to do with the dampener crank relationship.

 

[BSB67]

OK. Can the balancers be installed to the wrong crank?

yes, as someone already mentioned

 

[BMosely]

Sorry to be absent, took the kids camping and mudding this weekend. Here is the ticket. They can provide an external balanced flywheel.

 

[1 Wild R/T]

http://www.440source.com/dampers.htm

 

[khryslerkid]

http://www.440source.com/dampers.htm

Double post.

I see a lot of people not reading all the posts.

 

[Chukar]

Thanks

The 70-72 forged crank big rod engine had a thin damper that has an offset weight, it is externally balanced...

Here's a standard 440 internally balanced damper next to a 70-72 big rod externally balanced damper

And a side shot of the big rod damper.... AKA Sixpack damper

View attachment 1019413

View attachment 1019414 View attachment 1019413

The cut ring type dampener seems consistent with a forged crank common on 68 440 motor

 

[Chukar]

Look through these balancers closely. There are subtle differences between a couple but you should be able to identify yours and tell by the description what you have.

http://www.440source.com/dampers.htm

The cut ring dampener I have looks like it’s consistent with a forged crank Common to 68 440 motor. Thanks

 

[Chukar]

Triple nope. I just don't understand any discussion about a pulley bolt pattern as it has nothing to do with the dampener crank relationship.

Understood dumb question

 

[Chukar]

Be wary. Most forged crank motors were internally balanced. All cast crank motors are externally balanced. The exception are the steel crank motors with the heavy "six pack" rods. They used an external weight package.The 69 sixpacks used LYrods, so internal. 70 and 71 sixpacks used the heavy rods, and the heavy rods also appeared in later, non-sixpack motors. They used a different weight package than the cast crank motors.
I would suggest pulling the pan and seeing what you have. That way, no unpleasant surprises.

Thanks for heads up
I pulled motor and I’m told it has a steel crank and the heavy six pack rods , but not properly balanced Suggestions? It has 906 heads and pistons that are about 8.5 to 1 I’m thinking I want that up around at least 10 to 1 ?

 

[Chukar]

Absolutely Wrong!!! A 66-69 440 including the 69 440-6 are all originally internally balanced....

A 70-72 440-4 along with 70-71 440-6 engines are externally balanced but it is a fairly small balance weight on the damper & flywheel/torque convertor... They run a forged crank but they also run heavy rods

73 & up cast crank 440's are all externally balanced with a big weight on the damper & flywheel/torque convertor....

So I’ve pulled motor. It does have the heavy six pack rods But split ring dampener and no weight on converter. Prolly the vibration right?

 

[Chukar]

The 70-72 forged crank big rod engine had a thin damper that has an offset weight, it is externally balanced...

Here's a standard 440 internally balanced damper next to a 70-72 big rod externally balanced damper

And a side shot of the big rod damper.... AKA Sixpack damper

View attachment 1019413

View attachment 1019414 View attachment 1019413

Pulled motor. It has the heavy /six pack rods but the the dampener is the split ring no weights on converter. That’s my vibration right?

 

[moparedtn]

If I may, my own stupid question:
There is no difference in the mounting point on the snout of a forged vs. cast crank in a 440
for where the balancer is mounted, correct?
In other words, can someone can install a balancer for an externally-balanced crank onto a forged
crank snout?

 

[33 IMP]

So I’ve pulled motor. It does have the heavy six pack rods But split ring dampener and no weight on converter. Prolly the vibration right?

If you have a heavy "sixpack" rod motor, and a neutral balanced balancer, and no weight on the converter or flexplate.... yes that is your vibration problem.