They say they are using a gt-60 which I thought was as big as they get unless you get into power generation equipment. Thier setup used twin turbos in their drag videos and then they switched to a single so I assume they did it for a benefit of power. Then again p-port exhaust comes out at 1800 deg F and is well into the supersonic flow velocities. Maybe it just is to violent for spaced studs like that. Dunno.