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IAG Performance

IAG - Subaru 04-07 STI/05-06 LGT/04-05 FXT - 1000+ EJ25 Closed Deck Long Block w/ Stage 5 Heads

IAG - Subaru 04-07 STI/05-06 LGT/04-05 FXT - 1000+ EJ25 Closed Deck Long Block w/ Stage 5 Heads


Regular price $16,537.99 USD
Regular price Sale price $16,537.99 USD
Sale Sold out
Shipping calculated at checkout.

The IAG 1000+ Long Block is a complete, valve cover to valve cover, crate engine. It is the perfect option for ease of installation and gives you a premier "drop-in" engine.

This kit will support up to 1000+BHP applications. IAG's break-in instructions MUST be followed and the package must be professionally installed for the 12 months / 12k mile warranty to be applicable. All IAG Short Blocks are balanced and blueprinted.

Closed Deck Includes:

  • Case Halves - Converted to Closed Deck from brand new OEM Subaru case halves, bored and honed to 99.75mm.
  • Pinned Mains - Machine case for 9.5mm pinned mains and lined honed.
  • Fire-Lock - IAG Fire-Lock receiver groove machining, latest solution to prevent head gasket failure on high horsepower and high boost Subaru's - *IAG Fire-Lock head gaskets required
  • Head Studs - Machined for 14mm Head Studs.
  • Pistons - IAG-Spec JE FSR 99.75mm 2618 Forged Pistons, Electroless Nickel Plated Tops & Ring area, Ring Set, .250" / .927" H13 Wrist Pins, Clips, (Perfect Skirt Coating and Offset Wrist Pins)
  • Connecting Rods - IAG-Spec Tri-Beam Connecting Rods with ARP 625+ Rod Bolts.
  • Rod / Main Bearings - ACL or King Race Bearings.
  • Crank - Billet Crank by Callies
  • Case / Main Bolts - ARP Main Bolts.

  • Stage 5 Heads:
  • Heads - Brand New Subaru OEM WRX STI Cylinder Head Castings
  • Machine Porting - CNC Ported Intake and Exhaust Runners
  • Intake Valves - Ferrea 37mm (+1mm) Comp Plus Intake Valves
  • Exhaust Valves - Ferrea 33mm (+1mm) Comp Plus Exhaust Valves
  • Springs / Retainers - Ferrea Dual Valve Springs & Titanium Retainers
  • Keepers - Ferrea Valve Keepers
  • Guides - Ferrea Copper / Bronze Valve Guides
  • Valve Seals - Ferrea Valve Stem Seals
  • Lifters - OEM Lifter Buckets
  • Camshafts - GSC Stage 3 Billet Camshafts
  • Multi-Angle Valve Job
  • Machined Cam Lobe Clearance
  • Drilled For 14mm Heads Studs
  • Resurface
  • Ultrasonic Cleaning
  • Final Lash

  • Gaskets, Hardware & Accessories:
  • Head Studs - IAG / ARP 14mm Set
  • Head Gaskets - IAG Fire-Lock
  • Valve Cover Gaskets - OEM
  • Cam Seals - OEM
  • Valve Covers - OEM
  • Wrist Pin Seal, Rear Main Seal & Separator Kit
  • Crankshaft Woodruff Key

  • *If you need more information about this engine block, please don't hesitate to call us at 503-619-0055 for expert advice.

    *All IAG Engine Blocks are engineered, balanced, and blueprinted per your order and shipped in crates by freight trucks. Please allow an extended shipping duration. Contact one of our specialists for more information.



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