CMbuildz catless primary downpipes Stinger/G70BEST Downpipes on the market for the stinger G70 3. 3tt platform. CMBUILDZ is finally releasing primary downpipe options for the Stinger Genesis 3. 3TT platform. Its been a while coming but its finally here. These are all 304 SS construction tig welded. All downpipes come Black Cerakoted to control heat management without having to heat wrap. 304 stainless steel port match inlet flange for max flow tig weld and backpurge Black cerakote comes standard