I've been thinking about changing a few things on my car. Currently stock 7bolt with a FP T28. Thinking about going with either a 1g slightly ported head, 1g manifold, 1g TB or bigger turbo ie. 20g or 50trim(street car). I already have the manifold and TB so aquiring the head is the only thing to add to the list on that. What sort of gains would be more significant?

I like having a sleeper car, so I am leaning toward the head swap. Just curious as to what sort of gains I might see because of it. Any help is appreciated.

The turbo will show you more gains. I would go with the 50 trim myself. That was a great street turbo. The 20g is proven to be a good turbo too, but it is more $$$ usually.