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IAG Performance S3X FA20DIT Short Block Stage 3 Extreme FA20 DIT Subaru Closed Deck Short Block

Engine Short Block


IAG Stage 3 Extreme FA20 DIT Subaru Closed Deck Short Block for 2015-21 WRX.

  • All IAG Short Blocks are balanced and blueprinted.
  • Compression Ratio: 10.6:1 (stock compression) on standard gasket thickness.
  • The IAG Stage 3 Extreme Short Block has a power output rating of 800BHP
Pricing: $5,999.99

Free ground shipping on all order over $100.00 (some exclusions may apply)


Subaru: WRX 15 - 21, Subaru: Forester 14 - 18

Stage 3 Extreme FA20 Includes: Case Halves - Converted to Closed Deck using brand new Subaru OEM case halves, Case Machining - Modified for improved oiling Case Machining - Bored and honed to 86.25mm, O-Ringing - Machine and O-Ring Deck Surface Head Studs - Machine Case to 1/2" head studs - Head studs are sold separately, Pistons - IAG-Spec 86.25mm Forged Pistons, Ring Set, and .150" x 2.250" Chromoly Wrist Pins. Connecting Rods - Manley I-Beam / ARP2000 Rod Bolts, Rod Bearings - ACL or King XPG, Main Bearings - IAG Spec, Crankshaft - New Subaru FA20 DIT WRX crankshaft, Case / Main Bolts - Standard Subaru case bolts - OEM Oil Plug - comes preinstalled at the oil pan location

IAG Stage 3 Extreme FA20 DIT Closed Deck Short Block The IAG Stage 3 Extreme short block starts with new Subaru FA 2.0L engine case halves that are machined for improved oiling. Then IAG machines the case halves assembled together in our Haas VF-4SS CNC mill to accept the IAG CLOSED Deck Inserts that transform the block into a solid deck. The unique inserts feature small passages that allow needed coolant flow to the deck surface. The case halves are then CNC machined with O-ring receiver grooves around the bore surface as well as drilled and tapped to accept 1/2" head studs that greatly reduce head gasket failure during high cylinder pressure scenarios. Next, the short block is Deck Plate bored and honed that to 86.25mm on our in-house Sunnen SV-30 the most advanced automotive cylinder hone available. IAG's in-house honing process is able to set piston to wall clearances tighter for a quieter running engine. The short block is measured and assembled using a new 2015-20 Subaru 2.0L WRX crankshaft that is matched to King main bearings. Manley I-Beam rods with ARP2000 rod bolts are utilized along with King or ACL rod bearings. The case halves are sealed with new OEM case bolts and sealant. Finally, IAG-Spec 86.25mm forged pistons are spec'd and installed along with an OEM oil plug finishing off the short block.


  • IAG-ENG-1313
  • IAG-ENG-1313
  • 887753778093
  • IAG Performance
  • New


Shipping Information

  • Item Requires Shipping
  • 105.0 lbs.
  • W19.0000” x H16.0000” x L19.0000”
  • Free ground shipping on all order over $100.00 (some exclusions may apply)

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