Just got a 429 out of a 72 Ltd and was wondering is it internally balanced as far as the flywheel goes? Im told the blocks from 68-88 were but i thought id ask on here to be sure.

 

I think it was till 78, But in 79 they changed to internally balanced.

 

Internaly balanced up to 1972 after that externaly balanced

 

mid 79 was when they changed. very easy to tell. the externally balanced motors will have a big weighted spacer behind the front balancer/pulley assembly. looks like a hatchet.


not 72.

rgds
Mike

 

Post ALL the Casting numbers from the block near the starter...including the actual Date of casting numbers.

 

basic is if the block casting number above the starter is D9TE it was external balanced, any other block casting number should be internal balanced.
Any 429/460 that truly was original in a car is internally balanced.