Intake Manifold Cable Throttle Reverse Orientation - Subaru 99-00 WRX/STI

Intake Manifold — Cable Throttle, Reverse Orientation, Subaru WRX/STI 1999–00

The Process West Billet Intake Manifold is the result of years of research, multiple prototype iterations, and an uncompromising design process. It represents the highest level of induction engineering available for the Subaru WRX and STI, where precision aesthetics and outright performance are equally non-negotiable.

Billet construction throughout.

The manifold features a full billet plenum with generous billet bell mouths and thick-wall polished CNC mandrel bent tube components, assembled with high-end TIG welding. This construction makes it suitable for boosted applications up to 100psi, a specification no other product in this category comes close to matching in terms of strength and finish quality.

Engineered for real performance gains.

The plenum volume and runner length combination has been optimised for strong low and mid-range torque without sacrificing top-end power. Even on a stock setup, customers regularly see gains of 10% or more. The performance advantage over competing aftermarket intake manifolds is significant enough that customers have removed other systems to fit the Process West unit.

Reverse orientation, cable throttle.

This configuration features a reverse orientation throttle body position with cable throttle actuation, making it suited to the 1999–00 GC8 WRX and STI and specific intake setups where the standard orientation is not practical. Custom throttle flanges are available on request for specialised applications.

Broad compatibility.

The range is modular, covering everything from the MY99 GC8 through to the latest WRX and STI models. For performance builds not requiring air conditioning, the Track version manifold is recommended and can be supplied with shorter billet TGVs for increased power in the upper rev range.

The pinnacle of induction for the Subaru WRX and STI.