[1995MGTS]

First time I had my car dynoed, the guy before me had an early 90's LX with nothing but an S-trim and o/r h-pipe, the rest of the car he said was bone stock and it looked it. He showed me his dyno sheet. 320rwhp/330+rwtq (not sure on the torque but it was in the 330's). Not sure what pulley he was using on the S-trim either but it does show what a good tune can do.

So I think its possible you could hit 350rwhp with your mods and a good dyno-tune. Intercooler isn't necessary to do so. Might be safer but not mandatory. Good luck.