Many Japanese domestic market (JDM) engines are known for their reliability, endurance, and power. Added to that, these engines are often very lightweight. If you’re lucky enough to score one of the best JDM engines, you just might have the beginnings of a fast sleeper car on your hands.
Top 10 JDM Engines
Reliability is not the only thing these engines have going for them. Many are surprisingly powerful, with lots of torque. The output figures of the best JDM engines are often different from the stats for the same car’s engine when it’s released in other markets.
This sneaky power and huge aftermarket for performance parts have made JDM motors fan favorites around the world. Many of these engines have a near cult-like following. Read on for a list of the ten best JDM engines — as well as a list of the worst Japanese manufactured engines.
Honda B-Series
The Honda B-series included SOHC and DOHC inline-4 poppers. The SOHC versions were put into economy cars, while the DOHC were equipped as a performance option. The B-series was also the first time Honda used its SOHC VTEC (Variable Valve Timing and Lift Electronic Control) system.
The B-series family consists of four engines: the B16, B17, B18, and B20. Of the four, the B16 and B18 are by far the best JDM motors of the group (though the JDM B20B is pretty good). These engines can produce between 126 and 190 hp without modification. Additionally, the B16 has a redline in excess of 8,500 rpm.
The Honda B16B was specially manufactured for the JDM Honda Civic EK9 Type R. Despite the engine’s small volume of 1595 cc, it delivers a peppy 186 hp and is capable of revving to 8,900 rpm. When fitted to the Civic EK9 Type R, it was a fitting weapon.
In addition to its excellent performance, the engine was also very durable because it contained pistons that had less friction in the cylinder, a fully balanced crankshaft, lighter inlet valves, dual-layered inlet and exhaust valve springs, and, most importantly, a different short block.
Subaru EJ20
The Subaru EJ20 is a tough and durable powerplant. This JDM engine was used in the Subaru Legacy, Subaru Impreza WRX STI, and Subaru Forester for years. The EJ20 can be naturally aspirated or turbocharged. Of the two, the turbocharged EJ20 is by far the more popular.
Many fans of JDM motors refer to the turbo EJ20 as the EJ20T. Sounds reasonable, but Subaru actually designated the turbo engine JDM as the EJ20G. These engines made their way into the top performance packages of several cars, though the Subaru WRX STI may be the most notable of the group.
The Subaru STI motor has been a WRC rally circuit standout and is known for being ready to handle anything. The EJ20G has a power range from 220 hp at 6,400 rpm to 275 hp at 6,500 rpm.
Thanks to this engine, Subaru has often found itself in pole positions at rally events. With a long legacy of excellence, the EJ20G is highly regarded as one of the best JDM motors in history.
Nissan VR38DETT
Nissan’s VR series of engines is a group of DOHC twin-turbocharged V6s. The group has powered everything from GT-Rs to Jukes, alike.
The Nissan VR38DETT is the best-of-the-beast among these V6 stallions. This 3.8L, 24 valve beauty weighs a scant 600 pounds. And it is equipped with variable valve timing and a feedback control system to change the fuel/air mix based on engine load.
Nissan offered this beastie in the Nissan GT-R and the rare JDM Nissan Juke R — it was also used in the 2014 Nissan Infiniti Q50 Eau Rouge prototype, too. Buyers had their pick of 480, 550, or 600 hp if they opted for the top-tier twin-turbo engine. The VR38DETT takes the title for the most powerful option on our list of the best JDM engines.
Mazda 13B-REW
Mazda has been toying with Wankel rotary engines since the late 1950s. The first mass-produced version was the L8A in the Mazda Cosmo which debuted at the 1963 Tokyo Motor Show.
The 13B holds the distinction of being the most-produced Wankel engine. The 13B enjoyed a 30-year production run that ended in 2002. It has been in so many Mazda offerings that it has almost become synonymous with the automaker.
Perhaps the best version of the 13B is the 13B-REW. The 13B-REW is small, even as JDM motors go. Coming in at just 1.3L, its power is boosted by twin Hitachi HT-12 turbochargers. The primary turbo provides boost up to 4,500 rpm; then the secondary turbo comes online. This system marked the first use of a sequential twin-turbocharged engine.
The engines produced during the 2002 model year are capable of 280 hp — great output for a 1.3L. Mazda’s cars that come equipped with these best JDM engines and transmissions are an absolute blast to drive.
Mitsubishi 4G63T
The Mitsubishi 4G63 is a 2.0L version of the Mitsubishi Sirius engine. These JDM motors were placed in the Galant, Eclipse, Lancer, and several Mitsubishi pickup trucks.
The naturally-aspirated versions were well known for their fuel-sipping ways and long-term durability. They were never known for their exciting acceleration or top-end performance. That is where the 4G63T comes in.
The Mitsubishi 4G63T is the turbocharged version of the 4G63 and has powered Mitsubishi’s entries in the World Rally Championships for years. Great cars imported from Japan like the WRC versions of the Mitsubishi Galant VR-4, Lancer Evolution, Carisma GT, and Lancer WRC04 were powered by variants of this engine. It powered the Lancer Evolution Tommi Mäkinen drove on his way to winning four consecutive WRC titles.
Even stock, the 4G63T is beefy. In a 2003 Lancer Evolution, the output from a stock 4G63T is 271 hp at 6,500 rpm and 273 lb.-ft. of torque at 3,500 rpm. That’s enough to keep things exciting from behind the wheel.
Toyota 4A-GE
The Toyota A series of JDM motors is a family of inline-4s with displacements between 1.3L and 1.8L. Toyota began developing the series in the late 1970s with the goal of creating a line of the best JDM engines that could strike a balance between fuel economy and performance.
The A-series includes the first mass-produced DOHC, four-valve-per-cylinder engine, the 4A-GE. Toyota’s goal was to build a small volume unit that would be powerful while still being very economical and reliable. A mainstay in the JDM engine depot, this engine was developed over five generations.
The first iteration was called the Blue Top for the blue lettering used on the valve covers. These JDM engines had an output of 112 hp and made 97 lb.-ft. of torque. The Red and Black Top second-gen versions were capable of 115 hp and 98 lb.-ft. of torque.
The third-gen Red Top version of these JDM engines had an output of 123 hp and 110 lb.-ft. of torque. The Silver Top fourth-gen was capable of 157 hp and 120 lb.-ft. of torque. In the end, the fifth-gen Black Top version of the Toyota 4A-GE was capable of 162 hp and 120 lb.-ft. of torque. This version of the 4A-GE is highly sought after by tuners and has quite a parts aftermarket.
Nissan SR20DET
This is one of the more respected JDM engine and transmissions combinations to ever be produced. The Nissan SR20DET is a 2.0L DOHC turbocharged inline-4 with electronic fuel injection.
The SR20DET was used in several cars in the JDM market, and power varied by model. In its most fuel-efficient variation, it was capable 202 hp and 202 lb.-ft. of torque.
When given more power, as in the Nissan S15 Silvia, it was capable of 250 hp and 220 lb.-ft. of torque. Nowadays, this 16-valve powerplant is very popular among tuners.
Honda K20A
The Honda K20 is one of the most reliable JDM Honda engines on our list. It was originally built to have a long life in the family-focused Honda Stream. The base K20 was a sensible engine for a sensible purpose.
But, on more than one occasion, that sensibility got a little twisted with the Honda K20A that was used in the Civic Type R and Honda Accord.
When used in the Civic Type R, the VTEC engine’s output has ranged between 212 hp and 221 hp with torque ranging from 150 to 160 lb.-ft. It was also available in certain Honda Acura models, too, with exclusive JDM front clips.
Nissan RB26DETT
The Nissan RB line of JDM engines is a group of straight-6 powerplants built between 1985 and 2004. Displacement ranged between 2.0 and 3.0L. The RB family was used almost exclusively in the Skyline family of compact cars, sports cars, and compact executive cars.
One of the most exciting members of the RB family is the RB26DETT. These 2.6L JDM engines were used in the 1989-2002 Nissan Skyline GT-R. The 24-valve Nissan RB26DETT uses six individual throttle bodies and a parallel twin-turbo system using T25-type ceramic turbochargers. The first version of this engine was rated at 276 hp at 6,800 rpm and 260 lb.-ft. at 4,400 rpm.
By 2002, output had been increased to 276 hp at 6,800 rpm and 289 lb.-ft. at 4,400 rpm. These numbers may seem low, but the RB26DETT is very modification friendly. Tuners have found ways to coax upwards of 500 hp out of an RB26DETT.
Toyota 2JZ-GTE
With the best JDM engines as powerful as the Nissan RB26DETT and the Honda K20A on the market, Toyota was forced to respond in kind with the 2JZ-GTE. This DOHC straight-6 had sequential twin turbochargers with an air-intercooler to set the engine apart.
The Toyota 2JZ-GTE was first placed in the Toyota Aristo V for the 1991 model year — and the Toyota Lexus GS300 — but quickly moved to the Toyota Supra RZ. For the Supra, the 2JZ-GTE used recessed piston tops for a lower compression ratio and a cylinder head with redesigned ports, cams, and valves.
Like the Nissan Skyline GT-R, Supras with JDM engines had an advertised output of 276 hp; however, the Supra had 320 lb.-ft. of torque. When Toyota added VVT-i, torque jumped to 333 lb.-ft. In other markets, output was rated at 321 hp and 320 lb.-ft.
9 JDM Engines with the Worst Engineering Failures
There are at least a dozen other JDM engines that could have made our list — but while many lists focus on celebrating the best examples of a particular thing, we’re going to dedicate the second half of this article to the worst JDM engines, too.
Most of the time everyone wants to talk about the GOATs (Greatest of All Time) and debate which best JDM engine they’d swap into their favorite ride if money were no object. Would it be a Nissan RB-series from the famed Skyline GT-R? What about the Toyota 2JZ from the iconic Supra? Both are probably on everyone’s best JDM engines list.
But the elephant in the room that no one wants to talk about are the JDM engines that fall on the other end of the spectrum. These are the engines that might just be the worst Japanese engines of all time due to poor engineering.
Honda D-Series (Single Cam VTEC, 1.6L)
When first released, Honda’s JDM dual cam VTEC engine started some buzz which was accompanied by the hope that it would make its way across the pond to the U.S. market. Sadly, it never made it to the States with the dual camshaft formula.
Instead, the Honda Civic EX and Si arrived with a single camshaft VTEC engine. Though this engine was definitely a step up from the DX and LX trims with the non-VTEC engine, it seemed to be stuck living in the shadow of the DOHC VTEC of the Japanese domestic market.
And as many tuners tried to make the single camshaft engine a real performer, they found a lot of weak links in the engine. Those links included the connecting rods and smaller bores in the block. If you wanted to get significant power from the engine, it all had to be upgraded.
The aftermarket did give everything it could to make the engine scream, but as most found out the hard way, it was almost necessary to simply swap the engine with a better model if you wanted to have a shot at making more power.
Mazda 13B Renesis
The Mazda RX7 had a huge fan base that was deeply saddened when the RX7 left U.S. shores in 1995. Nine years later, that fan club rejoiced at the new Mazda RX8 with the 13B Renesis naturally aspirated engine.
The cheers didn’t last long, though, as the Renesis turned out to be a real dud. The engine touted a reduction in power to aid in fuel economy, but even that started to sour as owners screamed foul on the mpg ratings. The debacle turned into an all-out uproar, and Mazda went so far as to buy back some RX8 models to satisfy their consumers.
The aftermarket did put together some forced induction options for this JDM engine, but the cost was hard to justify as the performance couldn’t really compete with any other modified import in the same class. The Engine Management System seemed to fight against the changes anyway, and most RX8 owners chose to abandon ship for another chassis with some leftover heartburn.
Nissan KA24E (Single Overhead Cam 2.4L)
The Japanese market 180SX and S13 Silvia were huge hits in Japan and sparked a wave of attention from U.S. consumers when the U.S. version — the 240SX — made its way across the pond.
However, fans of the car were disappointed to learn that the turbocharged engine in the Japanese models had been replaced with the single camshaft engine common with the Nissan Hardbody truck. The engine did provide significant torque, but couldn’t muster the power of its cousin from Japan.
The iron block would hold significant power with forced induction, but the single camshaft wouldn’t cooperate. Fans of the 240SX chassis were happy when, after two years of dull performance, the dual camshaft KA24DE replaced the single camshaft E engine.
The E and DE engine are still referred to as a “truck engine” 30 years later, a stigma that will probably never go away. This engine suffered from too much hype and couldn’t deliver on the promises.
Toyota 4A-GE (Non-VVT Head Version)
The Toyota Corolla AE86 garnered a legion of new fans when the anime series “Initial D” gained popularity in the early 2000s. Fans flocked to pick up the chassis to build drift cars as seen on “Initial D,” but most were disappointed in the 4A-GE engine once they realized how wimpy it was in real life.
Thankfully, the AE101 chassis introduced a variable valve timing (VVT) head atop the iron block, but the new chassis had no RWD option to match with the new potential.
The aftermarket began to upgrade to individual throttle bodies, replace the throttle bodies with carburetors, or swap the new VVT engines into the older AE86 chassis to combine the new promising engine with a RWD option. Others left the engine as it was and went the forced induction route. Either way, this wasn’t a plug-and-play JDM engine option.
Toyota 1MZ-FE
The Toyota 1MZ-FE engine started its life with a lot of promise. It was used in a wide range of vehicles from the 1990s through the mid-2000s, and even had a supercharger kit available from Toyota Racing Development. The aluminum block contained steel sleeves and was topped with a variable valve timing head (VVT). In 1996, the engine even made Ward’s top-10 best engines list.
But, as many owners found out the hard way, though, not keeping a steady eye on maintenance and oil changes proved costly, as engine sludge build-up sent a number of these Japanese engines to an early grave. If engine sludge didn’t affect the engine, another killer proved to be head gasket failures with cracks in the aluminum heads causing overheating issues.
Consumers eventually started a class-action lawsuit because of the engine sludge and overheating issues. The engineers didn’t take into account their consumer wasn’t going to keep to a strict plan of oil changes, and that mistake cost the engine its place on the best JDM engine’s list and earned it a reputation as one of the worst.
Toyota 7M-GTE
The Toyota 7M-GTE engine was brought out with the 1986 Toyota Supra and carried into the 1992 release. The inline 6-cylinder was a later variant of the 5M and 6M series engines, and the “T” in “GTE” stood for Turbo.
The 7M showed an increase in displacement up to 3.0L and was meant to really put the Supra up against other factory supercars from JDM automakers. However, the 7M-GTE started to show reliability issues, especially when boost was dialed up on the factory engine.
With increasing reports of failed head gaskets and knocking connecting rods, the engine was later be phased out with the introduction of the 1JZ in the 1993 Supra.
Nissan QR25DE
The Nissan QR-series engine was the replacement for the beloved SR and the mediocre KA engines. It ranged in size from 2.0L to 2.5L, and was used extensively in Nissan’s global lineup.
One of the variations in the U.S. market was the Sentra SE-R Spec-V which showed a sign of weakness in its peak of popularity. The Sentra SE-R used the 2.5L variation common with the Altima 4-door sedan and featured an integrated catalytic converter that suffered from poor ECU tuning on Sentra models.
The Altima didn’t suffer the same issue, but it did have an issue with piston rings over the course of its life. Sentra issues also showed up as higher oil and water consumption, as well as loose screws on the intake plenum that would find their way into the engine combustion chamber for a meeting with the pistons and valves.
The piston ring issue on the Altima ultimately spurred a recall campaign, though the Sentra didn’t see similar action.
Subaru EE20 (Boxer Diesel)
The Subaru EE20 Diesel was supposed to be a complete innovation of the famed Boxer engine that Subaru fans already loved. This diesel engine was released in the Forester and Outback models and was advertised with lower emissions (38% fewer hydrocarbons and 60% lower carbon monoxide) over the competitive gasoline engine on the same models.
However, diesel engines produce significantly more soot than a similar gasoline engine, and in order to burn that soot out of the exhaust particulate filter, they needed to be run at full operating temperature for longer periods of time. Subaru’s engineers didn’t take into account that their target market lived mostly in town and didn’t drive consistently at full operating temperature.
As the urban drivers found out, their catalytic converters weren’t being purged as regularly as the engineers planned, and converters soon plugged and needed replacing. The aftermarket tried to get around the problem by adding performance chips, but that opened a Pandora’s box of issues that also caused the direct fuel injection to make holes in the engine pistons.
Mitsubishi 4G54B
The Mitsubishi 4G54B had a lot of promise but failed to deliver the goods. It sounded great on paper; it featured computer-controlled fuel injection and a single turbocharger, but it was hard to tune for more power and was prone to head gasket failures. Two fuel injectors behind the throttle body provided fuel for the engine, but this positioning had trouble with equal distribution to all cylinders.
Plus, the throttle body, intake manifold, and cylinder head couldn’t get enough air flow to really make significant power. The aftermarket never embraced the 4G54 enough to build and tune past the flaws, and fans started to move on to the 4G63 engine which was much more capable.
JDM Engines: Unlocking Potential
As easy as it is to blame poor engineering and design for all of the noted JDM engine failures, one of the hardest things to design for is the end customer and their particular use case. Though some engine designs looked great on paper, the customer was the one who proved which JDM engine design was capable of performing — whether as a stock daily driver or a tricked, tuned, and modified JDM street racer.
