454 gen question

[73SWBBB]

Does it matter what gen motor I get if I'm replacing the motor from my 73? I've located a 4 bolt main gen 4 gm crate fresh water marine engine with 30 hours on it. Guys selling for a pretty reasonable deal. Any thoughts would be appreciated.

[Dr_Snooz]

I think you mean Mark IV. Mark IV's were used in trucks through 1990, so there should be no difference from what you have. I would avoid Gen V blocks. The Gen V's somehow didn't include mechanical fuel pump bosses or clutch pivot studs. These things reappeared on the Gen VI blocks. I don't know if marine engines differ at all from regular engines, so I can't speak to that.

[thachevythang]

I've got a buddy with a 68 and he's got a high perf. marine engine in it right now. He came across a tore up boat at the impound and paid 500 bucks for it! Mounts and everything the same, bolted right up he told me so it shouldn't be a biggie. I think I've seen a post with a similar question on the forum before. Try a search.