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Crankshaft Balancing Question

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Crankshaft Balancing Question

lpaulmorgan lpaulmorgan
New User | Posts: 32 | Joined: 01/14
Posted: 05/14/14
06:30 PM

I recently bought a 67 400 motor that has an Ohio Crankshaft's forged 455 crank. The motor was assembled and dyno'd, and now I bought it from a guy before he installed it in his car. While trying to figure out wether I needed an internal or externally balanced flywheel, I discovered that neither Ohio Crankshafts or the engine builder balanced this stroker crank before installing it in the motor. Do these cranks need to be balanced for a street car, or is it only necessary for a race engine?

barneyformula barneyformula
Addict | Posts: 3306 | Joined: 01/07
Posted: 05/14/14
06:59 PM

The only way to know how out of balance it is, is to tear it down and get the assembly balanced. I wouldn't take the chance on an engine with a bunch of good parts.
A little help... 'cause we don't all have to learn the hard way!

My71 My71
Guru | Posts: 1261 | Joined: 02/10
Posted: 05/17/14
04:43 AM

Even factory cranks were balanced to certain standards based on the motors design and expected use. Steve's right.. Only way to know is to take it apart and take it into a reputable machine shop. Crank, flywheel/pressure plate (assuming it's a 4 speed), balancer, pistons and rods..