No no, GTM was doing the different housings for the different "stages".
Stillen is using one housing for all their kits. The difference in the stillen kits isn't power, its what comes with the kit. For example the tuner kit doesnt have fuel or tuning. Everything else remains the same as the normal kit. If I remember correctly the max psi from the Stillen SC unit is like 18psi, so I got room to explore