Harmonic Balancer internal or external

[Kev'C3]

H i everyone. On a ZZ4 350 crate engine is the harmonic balancer internally or externally balance? And is that the same with the fly wheel? Your help would be much appreciated!! Thanks Kevin.

 

[JPhil]

A 350" motor is internally balanced, you can use any old store bought harmonic damper and flywheel.
A stroker is externally balanced so you'll need a specific damper and flywheel balanced to the rotating assembly. You don't want to use those on an internally balanced engine.

 

[Kev'C3]

Harmonic balancer for ZZ4 350 internal or external

Looking in the GM performance parts catalog,it show ZZ4 350 as a externally balance engine! then I heard that the harmonic balancer are the same as any other SBC but with externally balance fly wheel. Is this possible?

 

[JPhil]

Yes. There are internal/external balanced engines, set up like that.
Let me be honest, I am no engine builder. My experience is only with the one in my car.

 

[Twin_Turbo]

Actually the 350 is partly internal balanced as the rear crank flange is also a balance pad. Being a zz4 and as such 1pc rms it does not have a balance pad and therefore a counterweighted flywheel or flex plate. Another reason for the bolt circle difference. The damper howevetr is for int bal. on a zz4.
As for stroker engines. Not all are externally balanced. Im building an internal balanced 396 sbc.

 

[Kev'C3]

Harmonic balancer for ZZ4 350 internal or external

Wow I always learn something new! thanks for the clarification on the ZZ4 H.balancer. Now I can spend money on something else!:yahoo: Thanks again Kevin!