Originally posted by krfrea
I purchased a rebuilt sbc 350 and it didn't come with a harmonic balancer. How do I know which size to put on it?
The casting number is 3970014, This tells me 1970-1976. also, how do you tell inf your crank is internal or external balanced/ Sorry for being so dumb but this is the first chevy for a ford man.

id measure from the timing tab on the front cover to the center of the front seal and find a bal. that would fit. if you know its a 350 shaft then its internal bal.