GrimmSpeed 38/40mm V-Band External Wastegate Uppipe STi 2004+(59001)
An External Wastegate (EWG) allows exhaust gases to be diverted prior to entering the turbo; creating quicker turbo spool. The GrimmSpeed™ EWG has a larger diameter than a stock internal wastegate; this allows the exhaust gas to be released faster, which improves boost control, maintains maximum boost longer in the rpm range. All of these together will give you a 10-40 HP INCREASE. Moving the wastegate out of the turbo relieves the turbo from the massive amounts of turbulence that the stock internal wastegate creates. The entire EWG Up-Pipe is made of 304 SS(flanges, flex, tubing) and has a pipe-wall thickness of 14 Gauge, this is the most "heavy-duty" pipe you will find. Many other pipes use cheap thin steel and are marketed as "super light weight", not us. The inlet size is 1.92" and the pipe tapers down to 1.72” which acts as a funnel as it moves into the turbo allowing for the smoothest transition and best air-flow quality. The one of a kind Triple Layer Flex Joint is not located in the bend, which adds to the life expectancy of the flex section. Our outlet size is a perfect match to the most common stock location turbos allowing for a smooth transition into the turbo.