IAG 800 CNC Pocket Ported Competition Cylinder Heads Package (Does NOT Include Kelford A "272" Cams, Cam Towers, Lifters & Rockers) - 2015-2021 Subaru WRX / 2015-2016 STI

IAG 800 CNC Pocket Ported Competition Cylinder Heads Package

 

GEARED TOWARDS WEEKEND RACING

Tailored for the weekend racer, the IAG 800 CNC Pocket Ported Competition Cylinder Heads offer a significant enhancement in flow compared to the IAG 600 heads. Ideal for vehicles with occasional track duties such as road racing, rally, auto-x, or drag racing, these heads are engineered to support up to 800 BHP with appropriate modifications. Featuring upgraded GSC +1mm Stainless Steel Valves, GSC Viton Valve Stem Seals, enhanced GSC Valve Guides, and Kelford Dual Valve Springs with Titanium Retainers, these heads deliver top-notch performance. For FA20 Heads, which differ in configuration from their EJ counterparts, the casting is divided into "lower" and "cam towers." The inclusion of Kelford "A" cams with IAG 800 Cylinder Heads comes with new OEM cam towers, rockers, pivots, and valve shim caps for a comprehensive upgrade package.

 

CONSTRUCTED WITH BRAND NEW COMPONENTS

Each IAG 800 FA20 DIT Cylinder Head Set commences with fresh OEM castings sourced from Subaru of America. 

Following a thorough visual inspection and the removal of OEM guides, the heads are positioned into our in-house Centroid 5-axis CNC Machine, renowned for its precision engine machining capabilities. The Centroid CNC executes a "pocket port" beneath the valves, expertly enlarging and blending the opening. This CNC porting not only streamlines the machining process but also ensures consistent port results that are challenging to achieve manually. Subsequently, the heads are drilled to accommodate larger 1/2" or 14mm head studs commonly used in high horsepower applications. To mitigate the risk of coolant leakage, OEM press-fit freeze plugs are replaced with threaded plugs after being tapped and threaded. GSC Manganese-Bronze valve guides, optimized to enhance airflow, are then pressed into position, followed by diamond-honing of all intake and exhaust guides in our honing station. The heads undergo further refinement in our Newen Valve Guide and Seat Machine, which executes a multi-angle valve job tailored to the flow characteristics of GSC's +1mm valves. Resurfacing of the heads' decks is carried out using our TS-3000 BlockMate to achieve a smooth, even finish. To eliminate machining residue and oils, the heads undergo ultrasonic cleaning before final assembly, which includes the installation of Kelford Dual Cylindrical Valve Springs and Retainers, accompanied by GSC Viton stem seals.

 

 

 

WHAT IS POCKET PORTING?

Pocket porting involves enlarging and blending the area beneath the valve seat, a crucial aspect of any porting process. Our Centroid 5-axis cylinder head porting machine ensures precise execution every time. Specifically, this technique focuses on enlarging and blending the region approximately 1" beneath the valve, facilitating a seamless transition and enhancing power output. Unlike other sections of the port, which may not require additional volume at these power levels and could potentially compromise airflow velocity, pocket porting concentrates solely on optimizing this critical area.