Made from an AA 500 Series Casting it comes STD with: Clean flowing cooling vanes, for maximum cooling through the head, and around the intake ports for increased HP and over all cooling. A modernized Combustion chamber, for increased head flow & performance. A second Full Fin, so you can Fly cut your heads deeper to achieve almost any desired Head CC volume needed. Blocked off rocker stud bosses, to eliminate the O-ring and stop possible oil leaks. Long reach 3/4 Inch Spark Plugs, to reduce the chance of cracking between the Valve seat and Plug

Engine: VW Type 1 2 and 3 1600 Dual Port

Springs: Dual High rev

Valves: 42mm Intake by 37.5mm Exhaust

Casting: AA Performance 500

Plug Size: 14mm (Replacement Bosch Number is W8CC or NGK is B5ES.)

Bore: 85.5, works with 85.5,87, and 88 slip in kits

Bore: 92, works with 88 thick wall, 90.5 and 92mm kits

Bore: 94, works with 92 thick walls K and M, and 94mm kits

Please Pick Bore size when ordering Above