I had a tp38/gt4202 twin set up on my truck made 472/860 @ 1200* liked it a lot. changed out the 4202 for S475 that set up worked great too. now I have a GTP38/S475 setup. I have ran .84 1.0 and 1.15 exhaust housing, no waste gate, cross drilled a 1.0 gtp38 factory style waste gate, a 38 mm...