TurboSource investment cast 310SS 74mm EFR IWG turbine housing.
This unit features a larger 1.0 turbine A/R to increase maximum horsepower while only giving up a little bit of response compared to the .92 Borgwarner model.
Back to back testing shows only a 75 rpm slower difference in response while in 4th gear, but a 25+ rwtq gain across the entire rev range once full boost is attained, and over 25+ rwhp( 13B 8374 test car ). 
This unit has much larger wastegate runners which drastically improves boost control, however we are offering an additional porting for those who desire maximum boost control over response. This entails CNC removing the wastagate runner divider to maximize flow, at the cost of 100rpms in boost response.
This unit features a 3" vband turbine discharge that is a a slip fit design. This allows interlocking downpipe flanges if desired ( not required). Direct bolt on unit, requires no other fabrication.