i'm getting a new bottom half and im reusing the heads but i don't know what kind they. the stock spark plugs don't fit so i took one out and its a "ACDelco 3" and its a platinum plug. if anyone can help me it would help
Oh god, I was joking when I said double humps, they can't be chevy, he said he was re-using them, so I assume they were on his engine, If I had to guess, I'd say they are old style 1960's 302 or 289 heads since they have a bigger spark plug.