Japan has long produced some of the finest automotive engines ever made. While this view is open to debate, the performance and durability records of brands like Honda, Toyota, Nissan, and Mazda make a strong case. That reputation explains why certain powerplants such as the Toyota 2JZ-GTE, Nissan RB26DETT, Mazda 13B, and Honda K24 remain favorites among fans worldwide.

Yet Japan did not stop at a handful of standout designs from the 1990s and 2000s. Across earlier and later periods, its manufacturers created many more engines that delivered outstanding results, even if they receive less attention than the units found in the most celebrated Japanese vehicles.

Rather than revisiting the well-known Toyota 2JZ or Nissan RB26, this overview focuses on engines that were often limited to the domestic market, overshadowed by successors, or simply overlooked. These units still deserve recognition for the performance they offer.

Toyota 7M-GTE

The 7M straight-six from Toyota earns its underrated label largely because of the immense fame of the later 2JZ. The 2JZ gained renown for its robust bottom end and vast tuning potential, leaving the earlier 7M with far less notice despite sharing the same straight-six layout and Supra heritage.

The 7M-GTE arrived in 1987 for the third-generation Supra Turbo. It displaced 3.0 liters and used a CT26 turbocharger with 6 pounds of boost to produce 232 horsepower and 254 pound-feet of torque. Those figures allowed the Supra to reach 60 mph in roughly 6.4 seconds and a top speed of 145 mph.

Compared with the naturally aspirated 7M-GE that made 200 horsepower, the turbo version added an intercooler, oil cooler, and revised ignition system. It remained in production from 1987 to 1992 and appeared in only the A70 Supra and the Japan-market second-generation Soarer. Even with limited applications, the engine delivered impressive output for its era.

Nissan VH45DE

Nissan engineering during the late 1980s and 1990s produced a wide range of strong engines, including the KA and SR fours, VG V6s, and RB sixes. The company also introduced a V8 that competed directly with Toyota's 1UZ-FE.

The VH45DE was a 4.5-liter naturally aspirated V8 built with an aluminum block, forged crank and rods, low-friction pistons, and a 10.2:1 compression ratio. It delivered 277 horsepower and 294 pound-feet of torque with a 6,900-rpm redline. Introduced in 1989, it powered the Infiniti Q45 until 1996 and the Nissan President until 2002. Many believe the true output exceeded the advertised figure due to the era's horsepower agreement.

Mazda 20B-REW

Mazda's three-rotor 20B-REW stands out as a rare engineering achievement. It was the only three-rotor rotary Mazda ever sold for road use and proved the design could suit both sports and luxury applications. Its sole production home was the Eunos Cosmo, a grand-touring coupe sold only in Japan from 1990 to 1995.

The 2.0-liter three-rotor unit produced an official 276 horsepower and 296 pound-feet of torque, with real-world estimates closer to the low 300-horsepower range. It was among the first engines to use a sequential-turbo system that improved both low-end response and top-end power. Despite occasional reliability concerns common to rotaries, its scarcity and output merit greater recognition.

Nissan S20

The S20 powered the original Skyline GT-R, yet it rarely receives the same praise as later RB engines. The story begins in the mid-1960s when Prince developed a 2.0-liter straight-six for the Skyline 2000GT. After Prince merged with Nissan, a detuned version of the race engine entered road cars and created the first GT-R in 1969.

The S20 featured four valves per cylinder, hemispherical combustion chambers, crossflow heads, and special aluminum pistons. It made 160 horsepower, an impressive figure for any Japanese car of the period, and remains an important chapter in GT-R history.

Nissan VG30DETT

The Nissan 300ZX and its VG30DETT engine illustrate how a capable powerplant can be overshadowed by its car. The 3.0-liter twin-turbo V6 arrived in 1989 alongside the Z32 chassis. While the naturally aspirated VG30 made 222 horsepower, the turbocharged DETT version reached the agreed 276-horsepower rating, with many sources suggesting closer to 300 horsepower in reality.

The iron-block, aluminum-head V6 helped the Turbo models achieve low five-second 0-60 times. Its layout foreshadowed the twin-turbo V6 configuration now common across performance cars worldwide, even if it lacks the emotional appeal of a high-revving inline-six.

Toyota 3S-GE

The 3S-GE served Toyota reliably across multiple decades and models. The first version appeared in 1984 in the Japanese-market Camry and produced about 160 horsepower. A slightly detuned version reached North America in the Celica GT-S with 135 horsepower.

Over five generations, Toyota and Yamaha refined the engine for vehicles including the Celica, MR2, Altezza, and Caldina. The final Black Top iteration represented the peak of development for this long-running naturally aspirated four-cylinder.