Chevrolet Small Block Harmonic Balancers for chevy engines 350 5.7Lv8 second link explains what they do and what they are used for;;;;;;; Crankshafts vibrate with a twisting motion due the torque variation that results as each cylinder fires. This vibration is at its worst at some critical RPM. On a V8, this RPM is typically in the 4-5000 RPM range. If you operate the engine at this critical RPM without a harmonic balancer excessive vibration will eventually BREAK THE CRANKSHAFT. DON'T LEAVE IT OFF. A harmonic balancer modifies the vibration characteristics of the crankshaft and flywheel assembly. They are made from of a heavy steel ring mounted over a thin layer of rubber on the outside of a center hub. The rubber acts as a spring. The ring twists on the rubber to cancel out crankshaft torsional vibration. Some energy is removed as heat in the rubber but the balancer's primary function is to store energy and return it to the crankshaft at just the right time to suppress vibration.

Chevrolet Small Block Harmonic Balancers for chevy engines 350 5.7Lv8 second link explains what they do and what they are used for;;;;;;; Crankshafts vibrate with a twisting motion due the torque variation that results as each cylinder fires. This vibration is at its worst at some critical RPM. On a V8, this RPM is typically in the 4-5000 RPM range. If you operate the engine at this critical RPM without a harmonic balancer excessive vibration will eventually BREAK THE CRANKSHAFT. DON'T LEAVE IT OFF. A harmonic balancer modifies the vibration characteristics of the crankshaft and flywheel assembly. They are made from of a heavy steel ring mounted over a thin layer of rubber on the outside of a center hub. The rubber acts as a spring. The ring twists on the rubber to cancel out crankshaft torsional vibration. Some energy is removed as heat in the rubber but the balancer's primary function is to store energy and return it to the crankshaft at just the right time to suppress vibration.

References:

http://www.ebay.com/itm/Chevy-350-Harmonic-Balancer-Vibration-Dampner-8-10-25...

http://chevelleengineer.home.comcast.net/~chevelleengineer/harmonic.htm

Mouse over image to zoom 5-7-350-CHEVY-GM-8-SOLID-BACK-HARMONIC-BALANCER 5-7-350-CHEVY-GM-8-SOLID-BACK-HARMONIC-BALANCER Have one to sell? Sell now Details about 5.7 350 CHEVY GM 8" SOLID BACK HARMONIC BALANCER

References:

http://www.ebay.com/itm/5-7-350-CHEVY-GM-8-SOLID-BACK-HARMONIC-BALANCER-/2719...

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