Stage 4 CNC Ported Cylinder Head Package for 15-20 WRX AW20 Castings (Cams / Rockers / Lash Caps Sold Separately). 2001-subaru-outback-base the heads are reassembled using

the heads are reassembled using GSC Billet S2 camshafts that are intended for vehicles making 500-700 wheel horsepower

Bilstein B16 (PSS10) suspension kits feature ride height adjustability with 10-stage manually adjustable dampers in an OE quality

All Mishimoto fan shrouds are significantly lighter than standard fan shrouds

The fitting ties the AOS to the PCV system

GTIN: 00887753779717

Stage 4 CNC Ported Cylinder Head Package for 15-20 WRX AW20 Castings (Cams / Rockers / Lash Caps Sold Separately). 2001-subaru-outback-base the heads are reassembled usingIAG's Stage 4 Cylinder Head Package for the 2015 20 WRX utilizes a CNC porting program for the AW20 heads which was developed over the past year and tested on the most successful high horsepower Subarus. The ported head package starts with brand new AW20 WRX OEM head castings directly from Subaru of America. The bare castings are visually inspected and the OEM guides are pressed out. The heads are then fixtured into our in house Centroid 5 axis CNC