Stagea used to be full split pipe exhaust with metal cat, gtr fmic and GCG highflow.
Total stock ecu, no tune at all. Just boost was upped to 1 bar with no R&R unless on really cold and oddly, also had to be foggy, nights. However as far as I know, the Skyline ecu tune is different to the stagea, I was surprized how little R&R i hit.
Stock stageas make about 120awkw, mine made 160awkw. With a DFA/SITC tune I would have made 200awkw pretty easy.
Turbo made a MASSIVE difference actually. The top end was improved SO much and lag not sacrificed.
So yes, I was running an upgraded turbo on a stock ECU.