I have a 79 Trans Am which currently has a Pontiac 350 from a 75 Firebird (not sure which model) and I put a piston through the block. I was wondering if anyone out there knows how hard of a job it would be to put a 455 from a 72 Buick Riviera in it.

It's likely the only issue you'd run into would be the engine mounts. But it's minor. The trans should bolt up thanks to the BOP bolt patterns.

Ok thanks and I found out it's actually a '73 455 I'm not sure if that makes a difference, and the engine had a minor tick before he pulled it, but the guy only wants $150 for it so I figure why not.

swapping pontiac and buick parts, wow this is the first time that I've heard someone going for this project - its gonna be interesting.
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