5 Underrated JDM engines

There are many well-known JDM engines like the Toyota 2JZ-GTE or the Honda K20A but today we are looking at some hidden gems.

For an engine manufactured in Japan to be imported abroad, the engine must comply with the laws of the destination country. Because of this reason, engines produced for the Japanese domestic market (JDM) differ from the engines exported.

Most people would understandably look for one of those famous JDM engines. But JDM engines have a huge follower base in western countries and they have restricted accessibility because of customs laws. Therefore those engines are really hard to get even when money is not an issue. This is where these underrated engines come in.

You can find an underrated relatively unknown JDM engine much easier (and much cheaper) than a popular one. If you choose wisely, you might even get a bigger output from some of these underrated power plants.

Let’s take a look at 5 underrated JDM engines which have great tuning potential.

1. Mazda 13B-REW

We start this list with a Wankel rotary engine of course. They are the most underrated engines around even though they really come alive on high RPMs. These engines are notorious for fuel economy and reliability, and are always fun to drive.

Wankel engines don’t need much modification and are very light. The 13B-REW is an upgraded 13B engine. It was first seen in late 1991 on the third generation RX-7. The main difference from its predecessor is that it has twin turbochargers, which was a first on Wankel engines at the time. It has solid metal rotors, four platinum-tipped spark plugs (two for every rotor), a free stream exhaust, upgraded cooling, and a better oil framework. It is also fitted with an aerial intercooler.

The first of the series produces 255hp. The second generation increased the horsepower to 265hp and in 1999 the third generation increased it again to 280hp. The 13B-REW was produced until 2003. It’s an interesting engine and is still famous among avid tuners for good reasons.

Which cars originally came with the Mazda 13B-REW?

• Mazda RX7 (1992-2002)

2. Nissan VH45DE

The Nissan VH45DE is a naturally aspirated V8 90° four-stroke petrol engine from the Nissan VH-family, first seen in 1990.

The VH45DE utilised a lightweight aluminum block with aluminum heads. This kept the weight and temperatures down and made it popular amongst tuners. Even though it had a huge lightweight advantage, it was only used in two heavy cars.

The VH45DE had variable valve timing also known as VTC when they were first built. Nissan tested the engine without the VTC to keep the power just under 280hp at first because of the Japanese manufacturers’ “Gentleman’s Agreement”. With variable valve timing, this engine delivered 310hp! The VTC was taken off of these engines completely in 1996 because of the USA’s tightening emission laws.

Despite it only being produced for automatic transmissions, it can easily be modified for manual transmissions with an aftermarket adapter. Nissan ended production in 2002 but V8 enthusiasts are still very fond of this power unit.

Which cars originally came with the Nissan VH45DE?

• Infiniti Q45 (1990-1996)
• Nissan President (1990-2002)

3. Toyota 3S-GTE

The Toyota 3S-GTE is a turbocharged in-line 4 cylinder engine from Toyota’s S series catalog. It was first used in 1986 and saw 4 generations made until 2007.

The first generation was introduced in 1986 and produced 190hp. The second generation came 3 years later in 1989 and produced 230hp. The third generation was introduced in 1993 and it boosted the hp to 255. On the fourth generation that was made in 1999, the engine had a 5hp increase which made it 260hp.

JDM spec of these engines famously had ceramic exhaust turbines which made it a fan favourite in Japan. Sadly Toyota didn’t use these engines on many models but the ones that do use them are great cars.

Which cars originally came with the Toyota 3S-GTE?

• Toyota Celica (1986-1999)
• Toyota MR2 (1990-1999)
• Toyota Caldina (1997-2007)

4. Honda B16A5

Honda’s first B16 Engines had a power output of 150hp. The Honda B16A5 is a JDM spec naturally aspirated in-line 4 cylinder engine. This engine is famous for its impressive redline at 8300rpm which is just a mere 100rpm less than the legendary Type R version B16B.

The B16A1, B16A2, B16A3, and B16A6 engines, which are also sub-models of the B16A model, were produced with 160hp, but the B16A5 engines produced between 1996 and 2000 were produced with 170hp. This easily shows the difference between a JDM engine and other specs. Honda only used this brilliant engine in one model but it gained popularity among the drivers who prefer automatic transmissions.

Which cars originally came with the Honda B16A5?

• Honda Civic Si-RII (1996-2000)

5. Toyota 7M-GTE

We know this is the second Toyota on this list, but they’re just great at building engines.

The Toyota 7M-GTE is a turbocharged in-line 6 cylinder engine that started its production in 1986. Although this short-lived engine ended production in 1992, 6 years was enough for it to make a name for itself. It only had one generation which pushed out 232hp.

This was Toyota’s first attempt at using a dual overhead camshaft design and was only used on two models, one of which became a legend over time. That is of course the 86-92 Toyota Supra.

The cast-iron engine block is incredibly strong which makes these engines perfect for tuning, many seeing 450hp+ reliably on stock internals.

Which cars originally came with the Toyota 7M-GTE?

• Toyota Supra (1986-1992)
• Toyota Soarer (1986-1991)