I read through many mods people do but not many say they change the harmonic balancer. If these are matched to the power rating on the engine, at what point do you change it, say on a 305 when mods have been done and the power output is near that of a 350.
Also how do you determine which balancer to use, material, brand, etc...

I am not looking into buying one, just would like to learn about it.
Thanks.

 

I think any time a engine is built and balanced you should a a aftermarket damper.A fluidamper is always my choose because you get less wear on the engine bearings and timing gear and it will control all vibration at any RPM.The fluid damper is made of a laser welded housing,a internal inertia ring,and viscous silicon fluid between the two that keeps things balanced.I think this is one of the best investments for the bottom end of a engine that will see alot of RPM's.

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Superman
Rev'n to Seven

 

Also, the stock balancers don't do to well over 4500. Usually. If the engine was built to go farther than that then the factory put a better one on. I am proof. I had one come apart on me and I never went over 5000.

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'82 Firebird, dead stock, 9 bolt disc rear, over 200,000 miles and still going strong, more to come...

 

I have a better question.....Is it actually a balancer (Contributing to the balance of the rotating assembly) or just a dampener (absorbing torsional vibrations), or a combination of the 2?

I have seen them called either Vibration Dampener, and harmonic balancer and was wondering if there is a difference!

[This message has been edited by JP84Z430HP (edited December 01, 2000).]

 

it absorbs shock put out from the crank to keep from ruining it.

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beau-t-ful yellow 85 iroc

 

Are they "the bigger the better"? I have a '66gmc truck with a 327 and it's balancer is thinner and a smaller diameter than the one on my z28's 305. Should I get a new one for the 327? - I know it'll rev past 5000 rpm

 

For an internal balanced engine, it doesn't matter. The only thing that does (apart from quality for racing) is the clearance for the timing pointer. Most (I say most because later engines I hear are external balanced) '80+ SBC engines (regardless of CID) used 6-3/4" diameter damper. So long as the assembly is balanced properly, any balancer will do.

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George P. Lara
1994 Z28 LT1 T56
1984 Z28 High Output
Member: SCCA, SCFB, SC3GFB
Chevy Info --> MadMike's