BB Vibration causes (harmonic balancer?)
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Melting Slicks
Joined: Nov 2004
Posts: 2,540
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From: Pineville Kentucky
CI 6-8-9 Veteran
BB Vibration causes (harmonic balancer?)
I used the harmonic balancer that was already on the short block from an automatic car on my built 454 and reinstalled the 4 speed flywheel from the old engine. Would that cause a vibration?
Team Owner
Joined: Jul 2001
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St. Jude Donor '11, '16-'17
I don't think so. I believe 454s are externally balanced, so both your flywheel and balancer need to be for an externally balanced motor. Since the balancer was already there, it's probably correct. What did your flywheel come off of?
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Melting Slicks
Joined: Nov 2004
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From: Pineville Kentucky
CI 6-8-9 Veteran
The flywheel came off of my #'s matching motor for my 73, the shortblock (and balancer) came out of a chevy truck (I think) I was wondering if the flywheel and balancer have to be "matched"?
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
What motor was the flywheel from ?
Basically the whole rotating assembly has to be balanced together, balancer, crank, pistons, rods and flywheel on an externally balanced enginem you can't just swap out balancers and flywheels like you can on internally balanced engines. THere are some ways to get around this, maybe others know
Basically the whole rotating assembly has to be balanced together, balancer, crank, pistons, rods and flywheel on an externally balanced enginem you can't just swap out balancers and flywheels like you can on internally balanced engines. THere are some ways to get around this, maybe others know
Thread Starter
Melting Slicks
Joined: Nov 2004
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From: Pineville Kentucky
CI 6-8-9 Veteran
Originally Posted by MotorHead
What motor was the flywheel from ?
Basically the whole rotating assembly has to be balanced together, balancer, crank, pistons, rods and flywheel on an externally balanced enginem you can't just swap out balancers and flywheels like you can on internally balanced engines. THere are some ways to get around this, maybe others know
Basically the whole rotating assembly has to be balanced together, balancer, crank, pistons, rods and flywheel on an externally balanced enginem you can't just swap out balancers and flywheels like you can on internally balanced engines. THere are some ways to get around this, maybe others know
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by MotorHead
What motor was the flywheel from ?
Basically the whole rotating assembly has to be balanced together, balancer, crank, pistons, rods and flywheel on an externally balanced enginem you can't just swap out balancers and flywheels like you can on internally balanced engines. THere are some ways to get around this, maybe others know
Basically the whole rotating assembly has to be balanced together, balancer, crank, pistons, rods and flywheel on an externally balanced enginem you can't just swap out balancers and flywheels like you can on internally balanced engines. THere are some ways to get around this, maybe others know
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 2,540
Likes: 1
From: Pineville Kentucky
CI 6-8-9 Veteran
Originally Posted by 63mako
The internally balanced engines use a neutal balance flywheel and balancer. I don't know a lot about externally balanced but the flywheels are weighted on one side with holes drilled in the weight to balance it. I believe the balancer is too. I think they are to be balanced as a unit, short block assembled with the flywheel and balancer. I know you just put this together and in the car. Would really suck to have to yank it out to balance. Someone will chime in that is more knowlegable on this. Good luck and hope you don't have to get the loader tractor back out.
Anybody have ideas?
Melting Slicks
Joined: Dec 2005
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454's are usually externally balanced. Reason being is there isn't enough mass on the counter weights to compensate for the rod and piston weight, so additional weight is needed on the harmonic balancer and flywheel/flex plate to balance the assembly. If you've got unusually lightweight internals, you can have an internally balanced big block. Whoever built the motor will be able to tell you how it is intended to be balanced.
Last edited by shafrs3; Mar 29, 2006 at 10:03 PM.
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Racer
Joined: May 2005
Posts: 470
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From: Amelia Ohio
I believe you are supposed to be externally balanced. 400ci and up typically are. My 383 is and there is an extra weight bolted to the back of the balancer and the flywheel end has an extra plate the goes under the flywheel. Good luck.
Chris
Chris
