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IAG Performance

IAG Performance 550 Short Block Includes: Case Halves

$4,459.44

SKU: I00A IAG-ENG-S550

Out of Stock
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
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Overview

The IAG Performance IAG-ENG-S550 is a 550BHP rated 2.5L Subaru Short Block designed for modified EJ25 Subaru engines. It features IAG-Spec JE 99.75mm Forged Pistons, IAG-Spec H-Beam Rods with ARP2000 bolts, and a new Subaru Nitride Treated 2017+ STI Crankshaft. Built with 100% new components, this short block is engineered to handle increased cylinder pressures and comes with a 12-month/12,000-mile workmanship warranty, extendable to 24-month/24,000-mile with certified installation and tune.
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IAG Performance 550 Short Block Includes: Case Halves

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandIAG Performance
Part NumberI00A IAG-ENG-S550

Videos

What IAG block is right for you?

What IAG block is right for you?
IAG 550 Ej25 Block

IAG 550 Ej25 Block
Don't Rebuild Your Broken EJ25 - Upgrade It!

Don't Rebuild Your Broken EJ25 - Upgrade It!
IAG Performance New Engine Line up

IAG Performance New Engine Line up
NEW SHORT BLOCK FOR MY STI!!

NEW SHORT BLOCK FOR MY STI!!

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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