Nope, they're totally different! The Buick is a good engine, but it's heavier than the Chevy, and won't wind as tight. Buick, Pontiac, Olds, and Chevy all produced 350 engines, and they don't share many, if any parts. Ditto on the 455's, with Buick, Olds and Pontiac producing different versions of that displacement, all different from each other, and Chevy's 454.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!