I'm not sure if this is what's meant by a mini-me swap, but the scenario is this:

Stock D16Z6, I/E (it's going to be I/H/E before I do anything though). It seems to be a very popular idea to put a Y8 head on this motor. I believe the Y8 uses bigger ports on the intake manifold, can I expect any significant hp gains from putting a Y8 head on there? Or any hp gains at all? Is it worth it (enough bang for the buck)? Why is it so popular?

 

"mini me" is where you thake a non v-tec d block and add a v-tec head and a y8 head on a z6 block i dont think it do you any good

 

That's not really what's called a mini-me, but meh.

Anyway, I think the z6 is generally liked for having better head flow while the y8 im is generally liked for have better im flow. But that's just my take on it.

 

what about just replacing the IM/TB with one from a Y8?

 

That's common and sometimes said to have noticable benefits:

https://honda-tech.com/zerothread?id=1018993