Once you swap in a new engine does that change what kinds of parts you need to buy for your 3rd gen. For example i will be putting in an 85 blazer engine into my 91rs. When i buy headers, do i still buy headers that are made for the 91rs, or do i need to go according to the engine??

I know this sounds stupid but just a little confused. Since all v8's are basically the same, it should stay the same correct.

 

Buy them for a rs. Gen 1 small block chevys are all interchangeable. It doesnt matter if it is a different year. As long as the heads have accesory holes you will be fine. only the early heads didnt have the acc holes.