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Air and Fuel› Intake Manifolds and Components

Process West

Billet Intake Manifold

Name: Billet Intake Manifold
Brand: Process West
SKU: PWIM004

$2,179.59

SKU: PWIM004

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Overview

It features a full billet aluminum plenum with generous billet bell mouths and thick-wall, polished, CNC mandrel-bent tube components. The manifold is TIG-welded and suitable for boosted applications up to 100psi.

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The Process West Intake Manifold – Stock Orientation is a high-performance component engineered for 2002-2005 Subaru WRX and 2004-2005 Subaru STI models. This manifold represents a significant redesign of previous generations, focusing on both aesthetics and enhanced performance. Constructed from full billet aluminum, the plenum features generous billet bell mouths, and the runners are made from thick-wall, polished, CNC mandrel-bent tubing. The high-end TIG welding assembly ensures robustness, making it suitable for boosted applications up to 100psi. This level of strength and detail is unmatched by other products on the market. The plenum volume and runner length have been carefully selected to provide aggressive low and mid-range torque while also increasing power at higher RPMs. Crucially, the plenum volume is substantial enough for significant performance gains while remaining compatible with the factory air conditioning system. This makes it an ideal solution for a streetable yet aggressive setup that retains essential comfort features. Tests have shown approximately 9% gains in torque and power on both completely stock engine/turbo/fuel system setups and highly modified setups running E85. For those seeking maximum power in the upper rev range, the street version can be supplied with shorter billet TGV's. The manifold is available in Raw/Polished or Black finishes.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

Brand	Process West
Part Number	PWIM004
Category	Air and Fuel

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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