Subaru Engine Replacement Guide: EJ25 Head Gaskets, WRX Swaps & JDM Options

Subaru Engine Replacement: EJ vs FA — What You Need to Know

Subaru makes some of the most passionate car communities in the world — and unfortunately, some engines with well-known failure modes. Whether you have a headgasket-prone EJ25 or a spun bearing in your WRX, JDM Alliance LA has the replacement engine you need in our Vernon, CA warehouse.

The EJ-Series (1996-2014)

The EJ engine family powered Subaru's most iconic vehicles for nearly two decades. Here's what you need to know about each variant:

• EJ25 (Naturally Aspirated) — The most common Subaru engine. Found in 1996-2011 Forester, Legacy, Outback, and Impreza. Known for head gasket issues on Phase 1 (1996-1999) engines. Phase 2 (2000+) is much more reliable.
• EJ20T (WRX Turbo) — The iconic 2.0L turbocharged engine from the JDM WRX. Never sold in the US, making JDM units the only option for true WRX engine swaps.
• EJ207 (STI) — The JDM STI engine. Twin-scroll turbo, more aggressive tune than the USDM EJ257. If you want more power without a full build, an EJ207 swap is your answer.
• EJ257 (USDM STI) — 2.5L turbo, found in 2004-2021 USDM STI. Prone to ringland failure on stock tune with significant power additions. JDM replacement units are available.

The FA-Series (2015+)

• FA20DIT — 2.0L Direct Injection Turbocharged. Powers the 2015-2021 WRX. More modern architecture than the EJ with direct injection and better fuel economy. Less aftermarket than the EJ but growing rapidly.

Subaru Head Gasket: Repair vs Replace?

This is the most common question we get about Subaru engines. For a Phase 1 EJ25 with head gasket failure, a JDM replacement engine often makes more financial sense than a head gasket repair — especially if the engine has high mileage. A quality head gasket job on a Subaru can cost $1,500-$2,500 in labor. A JDM replacement EJ25 from us runs $600-$1,000 and gives you a fresh engine with 40,000-60,000 miles.

Have a Subaru engine question? Call us at (442) 888-0318 or browse our Subaru inventory here.