Yes, it is a Chevy Caprice with Buick trim. I am assuming it is a 350 already. Some of them came with smaller motors and one of the smaller motor was a 4.3 Chevy V8. While this engine is a Chevy and is just a 350 with shorter stroke and smaller bore, the small bore is so small it will not permit the valves from some 350 heads to open in the cylinder. Edelbrock makes special high performance heads just for these small bore V8s if you do happen to have one of them. But if you do you would be better served to swap in a Chevy 350 or even a 383 or a big block if you are after power.