When it comes to JDM cars, two specific engines stand out even though they were earlier than most JDM engines present in modern vehicles today. The RB series and the JZ series.

RB Engine Series

The RB series was in production from 1985 to 2004 after Nissan cancelled the VG series V6. All engines in the RB series were produced as four-stroke inline sixes, the smallest being a 2.0-litre and the largest being a 3.0-litre engine. Engines in the RB series are the RB20, RB24, RB25, RB26, RB28, and RB30 with the RB26 being the most iconic of all.

RB20

This specific engine was first produced by Nissan between 1985 to 2004, the design coming from the previous L20A engine. It has some standard features with its predecessor, such as stroke and bore, but most of the components and specs are different from the L20A. The RB20 was produced with other specs, and all of them were (1998cc) 2.0-liter engines with an oil capacity of 4.8 quarts. All engines in the RB series feature cast iron cylinder heads and cylinder blocks with a bore 78mm bore length, 69.7mm bore length. The least powerful had 93 horsepower, and the most powerful had 212 horsepower with torque ranging from 105lb-ft to 195lb-ft when stock. Valvetrain for the RB20 engines was available in SOHC (single overhead camshaft) and DOHC (dual overhead camshaft)

Different variations of RB20 engine:

RB20E

This was the first engine in the RB series featuring SOHC technology with a power output of 120 horsepower to 140 horsepower at around 5500RPM to 5600RPM, depending on the year of production.

RB20ET

This is the turbo version of the RB20E engine. After the turbo was added, it boosted at 0.5 bar 7psi with a power output of between 145 horsepower to 175 horsepower at 5800RPM to 6000RPM. This depended on the year of production. This engine didn’t have an intercooler and featured SOHC technology.

RB20DE

This engine featured SOHC technology with a restyled head, individual ignition coils, an inlet system with a new ECU, restyled connecting rods, and a redesigned crankshaft. Power output was around 145 horsepower to 160 horsepower, depending on the year of production.

RB20DET

This is the turbocharged version of the RB20DE with a 0.5 bar (7psi) turbocharger. It features new 270cc fuel injectors, new pistons, new connecting rods, restyled camshaft, and cylinder head seals. Power output reached its peak at 220 horsepower for the RB20DET.

RB20DET-R

This is a racing-oriented version of the RB20DET. It is not that much different from the RB20DET.

RB20DE NEO

This eco-friendly version of the RB20DE could produce around 150-160 horsepower with minor tweaks done to it.

RB20P

This was the only engine in the RB20 series to use LPG (liquefied petroleum gas) with a power output of around 150-160 horsepower. This engine also features SOHC technology.

Pros and Cons of the RB20

Pros

The RB20 engine was available for cars first produced in the ’80s and ’90s. Its simple design made it a favourite during that era as it was easily customizable. Rev-matching capability, short camshaft design are among the features that made cars with the RB20 engine sell, and mechanics loved it a lot. The RB20 engine is also praised for its low maintenance costs. If well maintained using the correct oil and fuel, it can last for 200,000 to 300,000 miles with no significant issues. Tuning an engine generally reduces its lifespan. It is also the cheapest engine in the RB series

Cons

Faulty ignition coils, which led to misfires if not changed. It is recommended that you should replace ignition coils for the RB20 engines after around 45,000-60,000 miles. Lower torque figures in low rpm figures, and bad fuel consumption.

RB24

This is the rarest engine in the RB series and was manufactured using different parts from the RB series. For example, the engine block was from an RB25DE(T), the cylinder head was from an RB30, and the crankshaft was from an RB20DE(T). It also used Nissan’s carburetors instead of the ECCS (electronic concentrated engine control system) fuel injection system. This made the RB24 rev higher than the RB25 and the RB30. This engine was not produced for the Japanese market, one of the factors that make it rare.

This combination of components made the RB4 have a 2.4-litre (2428cc) inline-six configuration producing 140 horsepower and 145lb-ft.

RB25 Variations

This 2.5-litre (2498cc) engine in the RB series was available in the following variants.

RB25DE

Featured a DOHC (Dual Overhead Camshaft) technology with a power output of 175-210 horsepower depending on the year of production. Nissan made updates to the engine over time, which allowed all engines in the RB25 series to have more power and torque at low rpm.

RB25DET

A turbocharged version of the RB5DE came equipped with a turbo enabling it to make from around 240-250 horsepower

RB25DE-NEO

This specific engine was made to be the first LPG engine in the RB25 series and made from around 190-200 horsepower.

RB25DET-NEO

A turbocharged version of the RB25DE-NEO making around 270-280 horsepower.

Note that all engine variants available in the RB25 engine all had the DOHC technology.

Pros and Cons of RB25

Pros
  • Like the RB20, the RB25 engine is easy and inexpensive to maintain.
  • Easier to obtain more power with stock engine components
  • Better cylinder head design than the RB20
  • Over time it got better and better
Cons
  • It expensive than the RB20
  • The lower maximum RPM limit
  • The piston ring lands are weak and do not last for long, especially after undertaking a mod.
  • Harder to tune if you want more than 400 horsepower

RB26

This was the first engine to have twin turbos arranged in parallel in the RB series and was available in two variants. Cylinders remain six in an inline-six configuration and a 2,6-liter (2568cc) displacement.

Different variations of RB26 engine:

RB26DETT

This variant features a cast-iron block made of cast iron and an aluminum alloy cylinder head. This was the first time the cylinder head was made from the aluminum alloy in an RB series engine. Featuring six individual throttle assemblies instead of a single throttle assembly like other engines in the RB series. The two turbos are set to limit boost pressure at 0.69 bar (10psi), and some cars with this engine have boost limiters to keep the boost under 0.97 bar (14 psi)

Power output was between 270-315 horsepower depending on the year of production as Nissan continued to better their engines with time.

RB26DETT N1

This is a performance version of the RB26DETT developed by Nissan Motorsports (NISMO) for racing groups A and N. The RB26DETT block required too much maintenance when in a race car, and therefore, they designed the N1 block. They also balanced the crankshaft to ease the vibrations making the engine push 7000-8000rpm. The turbines in the turbochargers were different in the RB26DETT N1 as they were made of steel, whereas the RB26DETT were made of ceramic. This was due to the turbines becoming unreliable when used at high rotational speeds.

RB26DETT Z2

This is an RB26DETT derived engine and is also called the RB28 used in the Nissan Skyline GT-R (Z tune), producing 510 horsepower and 540lb-ft. It is boring and stroked by NISMO; thus, it increases displacement to 2.8 litres and uses the same N-1 block as the RB26DETT N1.

Pros and Cons of RB26

Pros

Easily tunable to achieve much more horsepower, especially if you have an N1 block. The stock block is also not bad.

The ability to rev to high figures shows the ability of the engine to make more power

Individual throttle bodies which offer superior throttle response and reduce restrictions through improved airflow

Cons

Lesser engine displacement than its competitor, the 2JZ (0.4l less)

Spare parts are expensive as they are rare, especially with the NISMO versions

If you want more power output from an RB6 engine, you will end up spending more.

Faulty oil pumps in all RB26 trims

RB30

This engine was produced to replace the 3.3-litre Holden 202 as it could no longer pass the emissions requirements test at that time. It was made in different variations for cars that it was put in.

Different variations of RB30 engine:

RB30S CQ

This is a carbureted SOHC engine making 135 horsepower and 165lb-ft, which was specifically put in the Nissan patrol series.

RB30E

Fuel-injected SOHC engine putting out 155 horsepower, 183lb-ft, and was first put in the VL commodore. This engine was also put in the Nissan Skyline R31 GTS1 and GTS2. Still, the GTS1 made slightly less power, and maximum power output was achieved at higher rpm numbers than in the commodore. The power output was reduced in the GTS1 due to an update in the exhaust setup but was increased later, and the GTS1 made 175 horsepower and 190lb-ft but at slightly higher rpm figures. The GTS2 made much more, but at even higher rpm figures, it made 190 horsepower and 200lb-ft.  

RB30ET

A turbocharged version of the RB30E using the same SOHC technology, making 201 horsepower and 218lb-ft. It was only made for the VL commodore. Holden had a contract with Nissan to supply engines, and Nissan couldn’t put it in any of their vehicles.

Another engine in the RB series is the RB30ET, but it was not produced by Nissan. It is a turbocharged RB30E with all components and internals from other RB series engines.

Apart from the radiator having a low header tank than the cooling system’s highest point, there were no significant issues with the RB30. This was only an issue in the VL commodore due to its sloping nose.

Tuning an RB series engine:

RB series engines can handle around 300-600 horsepower without having to change the internals. Most tune their engines by adding a turbo or a turbo kit on non-turbocharged versions and upgrading the turbos to a bigger size for the turbocharged versions. Getting a turbo kit is also a viable option. As they come with new seals, lines, waste gates, and new manifolds, all of which are mounted by a simple bolt-on procedure. Turbo kits are a cheap and straightforward way to increase power output and throttle response. If you are looking to push above 600 horsepower, you must upgrade the internals, such as the camshaft and cylinder heads. The block can also be reworked to sustain the power output. Another underrated mod on RB series engines is upgrading the fuel injectors, spark plugs, and air intakes. This increases the power output of the engine due to the improved combustion. When you tune an engine, it can reduce its lifespan. You need to carefully maintain it if you want it to last long, service it regularly and use the correct oil. Other mods that you can undertake to increase the engine’s power output include upgrading the downpipe, straight piping, or adding a sport/performance exhaust. These might not add much power output, but it’s better than keeping it stock. Such mods are mainly added after upgrading the turbo for maximum efficiency.

If you consider an RB swap ensure the engine and transmission mount are compatible with the specific engine. You can use the transmission that comes with that RB engine or use a compatible one. Some go to extreme levels and have a custom transmission built for an engine swap which is a good but expensive option. Having a transmission that can handle the power output of your engine is one of the significant factors you should consider, also upgrading safety features such as upgrading the brakes, which can handle massive engine power output. Before initiating any engine upgrades, check the engine’s condition and fix or upgrade worn-out components to prevent mishaps in the future. The purpose for which you will use your car also determines the power output you want to get out of your engine.


JZ Engine Series

Apart from Nissan’s RB series engine, the JZ series did not have many trims. Though, as it only had the 1JZ and the 2JZ, both of which had the same inline-six configurations as the RB series engine. This configuration similarity is what makes these engines get compared together. All JZ series engines were designed for longitudinal mounting; therefore, they were made for rear-wheel-drive use only. The 2JZ was the eye candy in the JZ series, being used in the Toyota Supra, which is Toyota’s most iconic JDM car.

1JZ Engine

This engine was produced from 1990 to 2007 and had DOHC technology with two belt-driven camshafts. It had a 2.5-litre (2592cc) displacement and was made in three different variations.

Different variations of 1JZ engine:

1JZGE

The first 1JZ engine in the JZ series. It produced 170 horsepower and 185lbft and was only available in a four-speed automatic transmission.

1JZTE

A turbocharged version of the 1JZGE and had three generations to it, each generation having updates over the previous.

1st generation 1JZTE- Twin-turbocharged engine with a parallel turbo arrangement blowing through a side mount. Power output was at 275 horsepower and 268lb-ft. Turbo turbines were ceramic, and therefore the turbos were unreliable at high figure RPMs. Turbo failure was also a problem due to the one-way valve, which resulted in blow-by gases getting into the intake manifold

2nd generation 1JZTE- This version was a 1st generation recall fixing turbo issues, but this only happened in Japan as this did not apply to engines outside Japan.

The introduction of VVTI and an improved cooling system were among the major updates made to the engine.

3rd generation 1JZGTE- had significant updates, but the most significant one was it didn’t have twin turbos. This had a single turbo setup and was more efficient due to a smaller exhaust port in the head, which spooled the turbo faster at low rpm figures.

Power output did not change regardless of the updates made to all generations of the 1JZTE.

1JZFSE

This engine was designed to reduce emissions and fuel consumption without affecting performance. The significant change that the 1JZFSE had compared to other 1JZ engines is its reworked cylinder head design with a narrow-angle with swirl control valves. This improved the combustion efficiency. Power output was at 195 horsepower and 183lb-ft

2JZ Engine

This also had an inline-six configuration but a larger displacement 3.0-litre (2997cc) larger than the 1JZ. It was produced in the following variations.

Different variations of 2JZ engine:

2JZ-GE

This engine had a power output of 210-230 horsepower and 210-225lb-ft depending on the year of production. It had an aluminum cylinder head and a cast-iron cylinder block, with VVTI technology which was introduced in the third generation of the 1JZGTE.

2JZGTE

Toyota’s 2JZGTE engine was produced to rival Nissan’s RB26DETT engine. It was put later in the Toyota Supra to rival the Nissan skyline GTR R34. It was a twin-turbocharged version of the ZJZGE, which was sequentially arranged and featured a side-to-side mounted intercooler. Japanese versions of the 2JZGTE had ceramic turbines for the turbo, while non-Japanese versions had steel. The power output for the Japanese model was at 227-275 horsepower and 320-335lb-ft depending on the year of production. For the non-Japanese market, power output was at 320 horsepower with the exact torque figures or slightly higher than the Japanese market version. The 2JZGTE was available with a 4-speed automatic transmission or a 6-speed manual transmission

2JZFSE

Was only available with an automatic transmission with the same features as the 1JZFSE. The same VVTI technology in the 2JZGE was also used in this engine made 220 horsepower and 220lb-ft.

Pros and Cons of JZ series engine

Pros

High figure horsepower capabilities

The inline-six configurations are tightly placed

A forged crankshaft that can hold massive horsepower figures

A square bore and stroke

Cons

Timing belt failure

The crank pulley came apart at high speeds

Turbo failure in the 1JZTE

Tuning a JZ ENGINE

Naturally aspirated JZ engines are for about 400-650 horsepower with an addition of a turbo or a turbo kit and without changing the internals depending on the engine’s condition. Toyota kept updating the JZ series engines, making them better and more durable over time. This made them a favourite among car tuners taking the limelight away from the RB series engines, especially the RB26 series, the closest competitor, the 2JZ engine. JZ engines are a favourite due to the large displacement; they have more than most RB series engines, and they can handle more power with stock internals. The only thing that is changed is the turbos. Intake, crank pulleys, and the timing belt. Upgrading the turbo valve in the 1JZGTE is also an essential tune if you have this engine

When it comes to swapping, make sure the engine and transmission mounts are compatible. If you don’t have a transmission that came with the engine, get a compatible one or, even better, get one built for the engine that can handle the engine’s power output. Also, upgrade the safety features such as the brakes and seat belts. Some even add a roll cage for protection in case of an accident.


RB26DETT vs 2JZ-GTE

Reliability

Toyotas are built to be reliable and so are their engines. The JZ series takes the win in this case as it is more reliable than the 2JZ. Even the eco-friendly version of the JZ series is much better than the eco-friendly version of the RB series.

Performance

Japanese 2JZ engine made more horsepower, the same case applies to Nissan. The Australian market RB30 made more power than other RB engines made for Nissan’s production cars. The only significant difference in performance is that the JZ series engines have a little more torque than the RB series. Performance-wise the RB26 is closely compared with the 2JZ due to the similarities between the two engines. There are no significant differences except that 2JZ has a balanced power output even in low figure RPMs.

Tuning capability

This can be divided into engine component strength and how much power the stock internals can hold.

The 2JZ internals can hold much more power with stock internals than the RB26, as the 2JZ can hold figures of up to 800 horsepower with stock internals. In comparison, the RB26 can hold a maximum of around 650-700 horsepower. Due to the lesser displacement in the RB26 can hold a maximum of about 211-250 hp/l. The 2JZ can hold a maximum of 266 hp/l.

Both engine blocks can hold figures of more than 1000 horsepower.

Swap and build

RB engine builds or replacements are much more complicated to find and much more expensive than JZ parts. This is because very few RB engines were shipped out of Japan compared to cars with JZ engines. JZ engines were available in many vehicles shipped out of Japan, thus establishing a market for parts and mechanics to learn and assimilate JZ engines. Besides the parts, buying an RB engine is expensive because they are rare, and the owners rarely sell. Most of the time, you will have to import it from Japan. The good thing is that Nissan resumed production of the best RB series engine, the RB26DETT, in 2019.

Appearance

Even though the 2JZ has more performance and tuning options than the RB26, the RB26 is still more appealing. Even other RB series engines are more appealing than engines in the JZ series. Mostly due to the aggressive and high-pitched sound they make. The fact that RB engines are rare makes them even more loved, and those who have an RB engine rarely let go of it. In the eyes of a JDM enthusiast, an RB series engine is much better than the 2JZ.

Conclusion

From an engineering and value perspective, the JZ series engines are better than the RB series engines. However, the RB series engines are more appealing to JDM enthusiasts due to their rare nature. The cars that came with the RB series engine are also rare and more attractive to JDM fans as not many were shipped out of Japan.