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Anybody know were I could pick up a Internal Balance flex plate for a 454 Gen 5. around So.Cal. area.
Thanks In Advance.........
 

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Sit N' Spin
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Anybody know were I could pick up a Internal Balance flex plate for a 454 Gen 5. around So.Cal. area.
Thanks In Advance.........
Did you have a factory crank converted to an internally balanced one or are you running an Eagle forged crank?
 

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Cobra shouldn't be tought to find in your area call me tommorow I'll try to get you some part numbers a 427/396 (nuetral balance 168 tooth deal) may likeley work if memory serves Tom
 

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From what I read in one of my many engine books...:D

Just because it's "balanced" doesn't mean that it's "internally balanced".

A stock factory BBC crank is EXTERNALLY balanced by nature. This means that the crank has to have a counterweighted balancer and flexplate, or an "externally balanced" type. What external balance refers to is that there is not enough metal mass in the crank to bring it to a neutral balance. So instead they balance the crank to an externally counterweighted balancer and flexplate, and since the balancer and flexplate are what contain the "balancing weights" and they are on the outside of the engine, they refer to this as "external balance".

In order to convert a factory BBC crank to INTERNAL balance, slugs of mallory metal have to be added to the crank. This is a very expensive procedure (in the $1,000's range) to have done.

If it's an Eagle brand forged crank, all forged Eagle brand BBC cranks are made from the factory as a neutral balanced crank. They make them heavier than they need to be because it's much easier to remove metal to final balance than it is to have to add metal to it.

Unless you payed thousands of dollars for mallory metal slugs, when you pay your machinist to balance a crank that is externally balanced by default (all factory BBC cranks are), this means that he will balance it to an external balance damper and flexplate combo and an external balance damper and flexplate combo MUST be used.

Just wanting to make sure that you are aware of this. Would hate to see you get the wrong type only to end up with a severe vibration that you can't troubleshoot.
 

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From what I read in one of my many engine books...:D


Unless you payed thousands of dollars for mallory metal slugs, when you pay your machinist to balance a crank that is externally balanced by default (all factory BBC cranks are),
Incorrect. 396, 402 427 BBC's are internal balanced and all share a common crankshaft. Flywheels and flexplates are also interchangable between SBC and BBC as long as you get the correct balance type for the engine.
 
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