Create a smooth sounding exhaust note while increasing horsepower and torque with the PERRIN E4-Series Big-Tube Equal Length Header.
*COMPLETELY REDESIGNED* The new PERRIN E4-Series Big-Tube Equal Length Header comes with collectors that have been designed for better exhaust flow while allowing the headers to be constructed much more accurately. The improved exhaust flow and more precise construction increases power and reliability. The new E4-Series also has a low-profile design, allowing for lots of ground clearance.
*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.
*PERFECTLY SIZED FOR MORE HP* 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 1.625" primary tubing that is expanded at the flange to fit the Subaru exhaust port size. This size tubing is perfectly designed for cars making more than 500WHP. You can see from our dyno graphs that there is a significant gain in horsepower and torque across the entire RPM band compared to an OEM Subaru header.
*FLANGES & PORT MATCHING* PERRIN Flanges are CNC machined from 304 stainless steel and counterbored on the back side to make 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.
*SOUND* Due to its equal length design, the PERRIN header will alter the tone of your exhaust. The exhaust pulses from the engine are equalized and spread out producing a smoother, more refined sound. A byproduct of the equalization is a significant reduction in the volume of your exhaust sound. Some describe the sound as being similar to an inline four cylinder engine exhaust.
*OIL PAN* Most headers collect on the passenger side of the engine, and due to space constraints, are not equal length and compromise exhaust flow. Because we use the added room provided by the oil pan (only on 2.5L turbo pans), we can create a smooth transition of the header primaries to the collectors, and collectors to up-pipe, providing more power and torque then the competition. 2.0L WRX engines will need the 2.5L STI oil pan install kit. Please shop our installation kits for more information.
2002-2005 WRX - Yes, requires oil pan with header cutout and oil pickup tube, and custom modification to the radiator line to the transmission.
2002-2005 WRX - Automatic Transmission Yes, requires modifications to radiator.
2006-2007 WRX - Yes, requires 2002-04 WRX oil cooler assembly and oil feed pipe.
2004-2008 Forester XT - Yes, requires oil pan with header cutout, oil pickup tube, 2002-04 WRX oil cooler assembly, and 2002-04 WRX oil feed pipe.
2009-2013 Forester XT
2005-2009 Legacy GT
CSF Radiator with Built-in Oil Cooler - No
*Pictures used for marketing purposes only, actual product may vary
Returns may be accepted within 14 days of purchase pending Return Merchandise Authorization (RMA). No returns or cancellations on special order items. All returns will be charged a 20% restocking fee, no exceptions.
To be eligible for a return, your item must be unused and in the same condition that you received it. It must also be in the original packaging. Item must be able to be resold as new. Several types of goods are exempt from being returned. Hazardous materials, fluids, greases, chemicals, and clothing are not able to return.
Free shipping is available within the lower 48 states for most orders totaling $199 or more. A free shipping option will be available during checkout. This offer is for delivery address in the continental United States and excludes shipments going to Alaska, Hawaii, Military Boxes, and items that require freight shipping.
Patterson Performance stocks a large quantity of items at any given time. Some items may require drop shipping from one of our various distributors. In stock items will ship within 1-2 business days. If you're needing your product quickly, please contact us to verify product availability before placing your order. Orders requiring additional verification (security concerns, incorrect information, etc.) may need additional processing time. Estimated shipping dates are not guaranteed and are subject to change based on inventory levels and manufacturer lead times. Backordered items are shipped immediately once available.
Items ship daily, If the item you ordered is not in stock, a member of our team will contact you via email / phone.
Patterson Performance will only ship to an address that varies from your billing address if payment is made via Paypal or a financing partner.
Patterson Performance ships from multiple warehouses throughout the United States, and sometimes from manufacturers overseas.
You can simply contact us via email / telephone for a live inventory check
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