Hello i was wondering if ram horn manifolds could replace the stock manifolds? I am doing this to get rid of the smog crap on them and dont want headers cause i dont want to have to do exhaust work. And i have read ram horns breath really well.

They won't fit a thirdgen.

what part wont fit? Is it cause they dont have any ram horns that have a diameter the correct size or? Cause arent the exhaust ports the same on a tpi as any other sbc?

The K member is in the way.

ok thank you! Is there any other manifolds that i can replace with my stock ones to get rid of the smog and possibly pick up som hp with it?

You can use the stock manifolds and get rid of the smog (assuming it's legal in your area to do so). Only other option is 3rd gen headers.