by Brant » 23 Feb 2006 15:02
I researched this way back and this is what I found.
72-74's were detuned (lower compression by diff pistons and other mods)
72-74's externally balanced - cast crank.
My engine was a 72 and had a cast, extenally balanced crank. This had a very late production date.
Now, many people have claimed that their own 72 engine had a steel crank and was balanced internally. The Theory of others (more than one I should note) was that to weed out the steel cranks - many would have carried over into the 72 year. So, many early 72 engines got fitted with some left over steel bad boys.
I believe it, made sence to me, anyways – seeing as they seemed to do this for many things - ex. wide seem vinyl tops.
later