Description

It's no secret that the OEM Subaru case halves, or "block," aren't exactly the strongest. IAG has developed a process to greatly improve the strength of the OEM Subaru FA20 Case Halves to combat the effects of high cylinder pressures brought on by increased power and boost. Our proprietary "Closed Deck" System works by supporting the top of the cylinder in the weakest areas and prevents movement and expansion which can lead to cracks and failures. Despite the additional material supporting the cylinder walls, there is no concerns with overheating or coolant flow because the area around the middle of the cylinder still maintains the same coolant area. The custom IAG closed deck inserts are machined with holes for oil and coolant to pass through the same as stock. Each IAG 800 FA20 DIT WRX Case includes machining for 1/2" head studs and a cylinder gasket "o-ring" groove to aid in head gasket sealing. If you're one of those people who prefer to do your own builds we now offer our legendary closed deck case halves for purchase separately. Simply install your crank, rods, and pistons to your own specifications and be confident that the case halves will take the power and prevent common cylinder wall failures. The IAG Closed Deck conversion is performed 100% in-house by our engineers and experts using state-of-the-art equipment. The IAG Closed Deck starts with a new OEM FA20 bare case. The case is loaded and fixtured to a 4th axis rotary indexer in our Haas VF4-SS CNC Vertical Machining Center. It is supported by the main journals using a precision ground 2-inch bar and tailstock which ensures the datum is the main journals. This method gives us a true reference point to perform all machining operations. A Rennishaw probe is utilized to check that the case is fixtured true, and once confirmed the machining process begins.

Specifications

What's Included

  • (x1) IAG 800 Closed Deck Converted Case Halves (Using brand new FA20 DIT Case / Stock Bore 86mm) *86.1mm Bore and hone additional and required before final assembly!
  • (x1) Machined for 1/2" Head Studs
  • (X1) Machined for Head Gasket "O-ring"

Compatibility

  • 2018-2021 Subaru WRX 6 Man
  • 2015-2021 Subaru WRX Base
  • 2018-2021 Subaru WRX CVT
  • 2021 Subaru WRX EyeSight
  • 2015-2021 Subaru WRX Limited
  • 2015-2021 Subaru WRX Premium
  • 2019 Subaru WRX Raui Edition
  • 2015-2016 Subaru WRX STI
  • 2017-2021 Subaru WRX Sport
  • 2017-2021 Subaru WRX Sport-tech
  • 2019-2020 Subaru WRX Sport-tech RS

It's no secret that the OEM Subaru case halves, or "block," aren't exactly the strongest. IAG has developed a process to greatly improve the strength of the OEM Subaru FA20 Case Halves to combat the effects of high cylinder pressures brought on by increased power and boost. Our proprietary "Closed Deck" System works by supporting the top of the cylinder in the weakest areas and prevents movement and expansion which can lead to cracks and failures. Despite the additional material supporting the cylinder walls, there is no concerns with overheating or coolant flow because the area around the middle of the cylinder still maintains the same coolant area. The custom IAG closed deck inserts are machined with holes for oil and coolant to pass through the same as stock. Each IAG 800 FA20 DIT WRX Case includes machining for 1/2" head studs and a cylinder gasket "o-ring" groove to aid in head gasket sealing. If you're one of those people who prefer to do your own builds we now offer our legendary closed deck case halves for purchase separately. Simply install your crank, rods, and pistons to your own specifications and be confident that the case halves will take the power and prevent common cylinder wall failures. The IAG Closed Deck conversion is performed 100% in-house by our engineers and experts using state-of-the-art equipment. The IAG Closed Deck starts with a new OEM FA20 bare case. The case is loaded and fixtured to a 4th axis rotary indexer in our Haas VF4-SS CNC Vertical Machining Center. It is supported by the main journals using a precision ground 2-inch bar and tailstock which ensures the datum is the main journals. This method gives us a true reference point to perform all machining operations. A Rennishaw probe is utilized to check that the case is fixtured true, and once confirmed the machining process begins.

  • (x1) IAG 800 Closed Deck Converted Case Halves (Using brand new FA20 DIT Case / Stock Bore 86mm) *86.1mm Bore and hone additional and required before final assembly!
  • (x1) Machined for 1/2" Head Studs
  • (X1) Machined for Head Gasket "O-ring"
  • 2018-2021 Subaru WRX 6 Man
  • 2015-2021 Subaru WRX Base
  • 2018-2021 Subaru WRX CVT
  • 2021 Subaru WRX EyeSight
  • 2015-2021 Subaru WRX Limited
  • 2015-2021 Subaru WRX Premium
  • 2019 Subaru WRX Raui Edition
  • 2015-2016 Subaru WRX STI
  • 2017-2021 Subaru WRX Sport
  • 2017-2021 Subaru WRX Sport-tech
  • 2019-2020 Subaru WRX Sport-tech RS

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