I have a 95 gs-t with some mods heres the list
1.Apexi N1 Catback exth
2.Injen Intake
3.Greddy Type-s Bov
4.Not a mod but I put it anyway Greddy Turbo Timer

I want to know what is a good turbo upgrade and if its smog pass one
I would like to get my car to 350 to 400HP

:biggrin:

That is the best list I found on the net.
http://www.dsmtuner.com/tuning-guide/2gturbo/

350 hp can be done with an Evo III 16g, but if you're looking at 400 hp you may want something a bit bigger...