Perrin Equal Length Header Subaru 2002-2014 WRX / 2004-2020 STI
Equal Length Design
The equal length design of the Perrin E4-Series Header produces smooth, balanced exhaust flow from the heads to the turbocharger giving you the best of two worlds: quicker turbo response as well as more horsepower and torque throughout the entire RPM band. While designed to fit to the factory up-pipe, our header will also mate with an aftermarket up-pipe that fits factory header and turbo, as well as any rotated turbo kits compatible with the factory header.
You won't see grossly over-sized tubing to make our header "look" impressive; this just slows exhaust gas flow and reduces response. This header uses 1.5" primary tubing that is expanded at the flange to fit the Subaru exhaust port size. This size tubing is perfectly designed for cars up to about 400 wheel horsepower.
Flanges and Port Matching
Perrin Flanges are CNC machined from 304 stainless steel and counter-bored on the backside for smoother transitions. Flange ports are sized properly to ensure exhaust coming out of the head has a smooth, unobstructed path to the tubes. The ports are not over-ported which would cause gaskets to burn out quickly. The tubes are expanded inside the flanges for a perfect fit and smooth flow of exhaust gases to the tubes.
Note: 2.0L WRX engines will need the 2.5L STI oil pan install kit.
WARNING: This product can expose you to chemicals, including Lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go towww.P65Warnings.ca.gov