IAG Stage 4 CNC Ported Heads w/ +1mm GSC Valves for 02-05 WRX 2.0L S20 w/ Chamber Matching(Cams / Lifters Sold Separately). 2020-subaru-wrx sti-sti The modified case halves are

The modified case halves are then measured and assembled using a new FA20 WRX / BRZ Subaru crankshaft that is matched to King main bearings

The block is then paired up with our Stage 4 Fully CNC Ported Cylinder Heads to deliver maximum flow for high hp applications

IAG-Spec H-Beam connecting rods and ARP rod bolts are utilized along with ACL or King race rod bearings

IAG Stage 1 Cylinder Head Package: IAG's Stage 1 cylinder heads are intended for those looking for a cost-effective OEM+ replacement

IAG 900 EJ25 Closed Deck Long Block w/ Stage 4 Heads: The IAG Performance Hand-Built Subaru EJ25 Closed Deck Long Block Engine Packages are a complete

IAG Stage 4 CNC Ported Heads w/ +1mm GSC Valves for 02-05 WRX 2.0L S20 w/ Chamber Matching(Cams / Lifters Sold Separately). 2020-subaru-wrx sti-sti The modified case halves areIAG Stage 4 CNC Ported Heads with +1mm GSC Valves: IAG's Stage 4 Cylinder Head Package utilizes a CNC porting program for the WRX STI heads that was developed over the past five years and tested on the most successful high horsepower Subarus. The ported head package starts with brand new WRX OEM 2. 0L S20 head castings directly from Subaru of America. The bare castings are visually inspected then fixtured into our in house Centroid 5 axis CNC Machine,