Internal balance crankshaft

Old 10-11-2007, 08:10 AM
Junior Member
Thread Starter
Join Date: Aug 2007
Posts: 10
Default Internal balance crankshaft

Hi all

Dose it requires to use harmonic damper when my crankshaft has internal balance.

Thanks for all
amal is offline  
Old 10-11-2007, 08:21 AM
Senior Member
Join Date: Sep 2007
Posts: 4,143

You don't HAVE to...but you least that's my opinion. Sprint car guys don't use them.At least none that I know do.
Tod74 is offline  
Old 10-11-2007, 11:22 AM
Join Date: Dec 2003
Location: mtn city TN
Posts: 37

i think you should run a balancer even if your engine is internaly ballanced,just because is lessens harmful vibrations,that can beat your bearings out, not unless it is on a engine that gets tore down alot
im no expert,so this is just my opinion, but there is alot of good engine guys here that will probably be chiming in soon with a answer for you
gearhead37683 is offline  
Old 10-11-2007, 12:47 PM
Senior Member
Join Date: Feb 2006
Location: VA Hospital, Dallas, Tx (214 302 1924) cell-972-464-7400
Posts: 540

A Harmonic Dampener is not a Balancer. It is just called a Balancer. I wish that name had never been stuck onto it, becuase it is confusing to a lot of people.

Only when the Harmonic Balancer has additional weights to one side of it is it sued in connection with the balancing. That was a GM and Chrysler brainstrom to use in engines thay did not have enough internal counterweights on. They counter balanced the crank by the adding of weights to both ends to in effect be like an additional counterweight on each end. Chevy used a weighted flywheeel and an offset weigth in the Harmonic Dampener, (Ar times also called a Harmonic Balancer). Chrysler added additional weights to the one side of torque convertor and also used a weight offset on the Harmonic Dampener. Then and only then is it used in connection with babancing.

A Harmonic Balancer is like a shock absorber to try dampening some of the harmful harmonics and occilations that all crankshafts are subject to the stresses of. Your crankshaft is literally twisting back and forth in your engine as the individual cylinders fire. The Harmonic Dampener serves to dampen that twisting action to not be as extreme.

There was a period of time when just about everyone began using the new idea solid aluminum balancers on the front of the crank, becuase the NHRA and IHRA had forbidden the using of factory style Harmonic Dampeners and nothing else was available. Guys started breaking crankshafts that had never had problems. Some guys got brilliant and just took the heavy surrounding outer ring off by heating it until the rubber gave away and ran it as a solid hub. Someone or someones made some small diameter aluminum hubs to use. Nothing worked as good as the old factory Harmonic Dampeners. Racers were breaking cranks.

The Industry got a new player named Fluid Dampener who made a blow proof, SFI Certified, Harmonic Dampener. and wow!, Crankshafts quit breaking. Soon later others made their own versions of a Blow Proof Harmonic Dampener and all was well again.

Sprint engines do have problems. Ask Bill.

Blower engines that do not use Harmonic Dampeners' crank life has been extended with the front crank support. Still they need the Dampener if possible.

Long winded, but hope it helps you make the right decision.

edvancedengines is offline  
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service