Turbine Housing TypeSelectt4, 0.80 a/r, twin scroll turbine housing with pneumatic internal wastegatev-band, 0.85 a/r, single scroll turbine housing with pneumatic internal wastegatet25, 0.85 a/r, single scroll turbine housing with pneumatic internal wastegatev-band, 0.85, single scroll turbine housing (requires external wastegate)t25, 0.64 a/r, single scroll turbine housing with pneumatic internal wastegatev-band, 0.85 a/r, single scroll turbine housing (requires external wastegate)t25, 0.85, single scroll turbine housing with pneumatic internal wastegate