Subaru’s unique horizontally opposed “boxer” engines hold an esteemed position among JDM enthusiasts. Models tuned specially for Japan produce cult-favorite powerplants combining the boxer’s innate torque, smoothness and sound with extreme output. Let’s spotlight the most legendary JDM-only Subaru engines.
- 1 EJ20G/EJ20K – The Impreza WRX STI Beating Heart
- 2 FA20 – Continuing the WRX Legacy
- 3 EZ30 – Outback XT, Legacy GT Spec B
- 4 EZ36 – Japan-Only Legacy Spec B
- 5 FA24 – Coming to America
- 6 BRZ/FR-S – Toyota and Subaru’s Joint Sports Car
- 7 A Decade Dominating WRC
- 8 Built for the Street and Track
- 9 The Character of JDM Subaru Engines
EJ20G/EJ20K – The Impreza WRX STI Beating Heart
The turbocharged 2.0-liter EJ20 defined Subaru’s rally pedigree for over a decade. Debuting in the iconic 22B Impreza, the EJ20G produced nearly 280 horsepower in street trim and over 300hp when racing.
This bulletproof turbo boxer powered Subaru’s 1990s WRC champions before transferring to the equally legendary Impreza WRX STI. Durable yet tuneable, the EJ20 anchored Subaru’s global performance reputation.
FA20 – Continuing the WRX Legacy
In 2014, Subaru retired the EJ engine in favor of the new direct-injected FA series. The FA20DIT retains the WRX STI‘s 2.0-liter capacity but nears 300hp using a large single turbo and intercooler.
A dual injection system balances fuel economy and power demands. Revised cylinder heads achieve higher compression and improved response. Paired to a 6-speed manual gearbox, the FA20 provides blistering acceleration and high-rpm pull continuing Subaru’s turbo boxer legacy.
EZ30 – Outback XT, Legacy GT Spec B
For larger sedans, Subaru developed special 3.0-liter engines like the EZ30 twin-turbo flat-6 exclusive to JDM models. High-end Legacy and Outback models used this smooth, powerful 6-cylinder making over 280 horsepower.
Later, the EZ30 R variant added variable valve lift and timing for greater output. These large boxers transformed Subaru’s practical wagons and sedans into legit sports models blending family utility with serious motivation underhood.
EZ36 – Japan-Only Legacy Spec B
A rare 3.6-liter EZ36 boxer exclusive to JDM paired with a 6-speed manual transmission and DCCD AWD system turned the Legacy Spec B into an undersung performance great.
Although only sold for one model year, the EZ36 hit an underrated 280hp while sounding fantastic. This largest JDM-only boxer represented the pinnacle of Subaru’s engineering capabilities for the time. Durability gains kept the EZ36 relevant in JDM models years after discontinuing overseas.
FA24 – Coming to America
Subaru’s FA24 2.4-liter turbo boxer broke tradition by first launching in the US-market Ascent SUV. However, JDM fans knew big potential lay hidden under its hood.
The FA24 finally emerges in the next-gen 2022 WRX producing 271hp, improving daily-driving tractability. All signs point to more power unlocked in future STI variants shared with Japan. Could the FA24 become Subaru’s next JDM tuning legend? Time will tell.
BRZ/FR-S – Toyota and Subaru’s Joint Sports Car
In a rare collaboration, Subaru co-developed its rear-drive 2.0-liter FA20 boxer engine alongside Toyota for the jointly produced 86/FR-S sports car. This high-revving naturally aspirated unit generates 200+ horsepower packaged in an ideal sports car chassis.
While less powerful than turbo versions, the FA20 finds its perfect home propelling this lightweight coupe. The project renewed appreciation for the inherent sound, responsiveness and flexibility of Subaru’s flat engines.
A Decade Dominating WRC
The competitive successes cementing these JDM Subaru engines as icons cannot be understated. Starting with the EJ20, Subaru won WRC championships every year between 1995-2003 – a feat unmatched since.
Durability under extreme rally abuse proved the inherent toughness engineered into Subaru’s boxers. These motors regularly achieved victories over more powerful but less reliable opponents.
Built for the Street and Track
While race-bred, JDM Subaru engines translate rally dominance into streetable power perfectly suited for Japan’s winding roads. Linear torque buildup off idle contrasts peaky Honda VTEC powerbands. The low centered mass also pays steady handling dividends.
Whether carving mountain touge or sitting in traffic, these special JDM boxer engines spotlight Subaru doing what it does best – combining robust engineering with usability. Their successes expanded the possibilities of Subaru’s unconventional flat engine architecture.
The Character of JDM Subaru Engines
Beyond the specifications, Subaru’s horizontally opposed design lends unique experiential qualities. The distinctive boxers emit a baritone mechanical thrum absent from other 4-cylinder engines. The unequal firing intervals produce an engaging rhythm.
This engine character feeds enthusiast passions and makes common driving events feel special. Subaru’s JDM boxers showcase refinement paired to personality that endears owners in contrast to bland transportation appliances. They reveal that character and competence can coexist beautifully under the hood.