1NZ-FE Poweredga15 (carb on injected)
in 2 deep, i am not sure about your engine, but normally an upgrade for carbuerated engines airflow intake would be webbers, side draughts, etc. then doing the exhaust side of things make sense. pm nismodriver. he's the proud owner of a vehicle with the same engine. he should be able to shed some light. also dave, rx, and the other gurus.