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IAG Stage 4 Cylinder Head Package w/ Combustion Chamber Mod Includes GSC S3 Camshafts - Subaru WRX 2002-2005

IAG Stage 4 Cylinder Head Package w/ Combustion Chamber Mod Includes GSC S3 Camshafts

Subaru WRX 2002-2005

IAG Stage 4 Cylinder Head Package w/ Combustion Chamber Mod Includes GSC S3 Camshafts - Subaru WRX 2002-2005
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Part # IAG-ENG-3045SCS3
$5,999.99

Ships within 8 days

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Features & Product Details

RallySport Direct now carries highly sought-after high-performance upgrades and accessories brought to you by IAG Performance. 

 

This is the IAG Performance Stage 4 CNC Ported Heads With +1MM GSC Valves And GSC Billet S3 Camshafts With Combustion Chamber Mod. 

These heads utilize a CNC porting program for the S20 heads that have been developed over the past 5 years, and they have been tested on the most successful high-horsepower Subarus. These begin as brand new S20 head castings directly from Subaru Of America, where they are visually inspected and then fixtures at IAG's in-house Centroid 5-axis CNC machine which is considered to be of the most advanced piece of precision engine machining equipment available worldwide. 

 

FEATURES:

  • Centroid 5-Axis CNC machined in-house at IAG
  • The Centroid ports the intake and hard to reach exhaust "dog-leg" port runners
  • Everything starts with brand new Subaru S20 head castings that are visually inspected
  • The Centroid 5-Axis offers consistent port results that are hard to achieve by hand
  •  

    COMBUSTION CHAMBER MODIFICATION

  • Once the Centroid completes the port process the heads receive the combustion chamber modification
  • The shapes of the chamber are machined to reduce compression and to improve the burn path
  • The heads then undergo a cam clearance machining process that removes material from the lifter area where large duration cam profiles are known to contact the castings
  • Short after, the heads are drilled to fit larger 1/2" or 14mm head studs which are commonly used in high-horsepower builds
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    COMPONENTS AND MACHINING PROCESS

  • The OEM guides get pressed out 
  • Installed are GSC Manganese-Bronze valve guides that are shaped to improve airflow
  • The intake and exhaust guides are then diamond-honed
  • The heads are fixtured with IAG's Serdi 3.0 Valve Guide And Seat Machine
  • All intake and exhaust seats are cut with a multi-angle valve job that suits the flow characteristics of GSC's +1mm valves
  • The head decks are resurfaced using IAG's TS-3000 BlockMate that cuts the aluminum to a smooth even finish
  • The heads are then ultrasonically cleaned to remove debris and oil from the machining process
  • The heads are then reassembled using GSC Billet S3 camshafts (rated to 700 HP)
  •  

    INCLUDES:

  • (2) Brand new Subaru S20 cylinder head castings
  • (8) GSC 37mm (+1mm) intake valves
  • (8) GSC 33mm (+1mm) SuperAlloy exhaust valves
  • (16) GSC Beehive springs and retainers
  • (16) GSC Manganese-Bronze valve guides
  • (16) GSC valve stem seals
  • (16) OEM lifter buckets
  • GSC Billet S3 Camshafts
  • IAG Performance CNC porting
  • Multi-angle valve job
  • Drilling for compatibility for 1/2" or 14mm head studs
  • Cam clearancing
  • Resurface
  • Ultrasonic cleaning
  • Bench lashed
  •  

    GSC BILLET S3 CAMSHAFT FEATURES:

  • 280-degree intake/exhaust duration
  • 241-degree intake duration @ 0.040
  • 240-degree exhaust duration @ 0.040
  • Intake/exhaust peak lift 11.20mm
  • Intake center-line - 110 degrees
  • Exhaust center-line 115 degrees
  •  

    Note:  Workmanship/parts warranty will only be available for professionally installed cylinder heads.

     

     

     

     

     

     

     

     

     

     

     

    Specifications

    Brand: IAG Performance
    Head Alteration Required: No
    Includes Camshafts: Yes
    Machining Required: No
    Material: Aluminum
    QTY: Package
    Retainers: Titanium
    Springs Included: Yes
    Valves Included: Yes
    Mfgr. Warranty: 12 Months / 12k Miles
    Condition: New Product
    Return Policy:
    Standard

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