th 350 or a 400

[nickdubrule41]

i have a tranny it was from a 1973 impalla or at least thats what the guy told me it was from. he said its a 350 but how do you tell a th 350 from the 400. and what is the vacume line that goes to the rear of the tranny do? it must be part of how it shifts right?well any help would be great thanks nick

 

[BranndonC]

http://www.maliburacing.com/auto_tranny_id.htm