Nissan RB engines

Nissan RB engine
RB30E in an R31 Nissan Skyline
Overview
Manufacturer	Nissan Motor Company
Production	1985-2004
Combustion chamber
Configuration	Straight-six engine
Displacement	2.0 L 2.4 L 2.5 L 2.6 L 2.8 L 3.0 L
Valvetrain	SOHC DOHC
Combustion
Turbocharger	Single Garrett T3 Twin Garrett T28-type ceramic turbochargers (RB26DETT)
Chronology
Successor	Nissan VR engine

The RB engine is a 2.0–3.0 L straight-6 four-stroke petrol/gasoline engine from Nissan, produced from 1985-2004.
Both SOHC and DOHC versions have an aluminium head. The SOHC versions have 2 valves per cylinder and the DOHC versions have 4 valves per cylinder; each cam lobe moves only one valve. All RB engines have belt-driven cams and a cast iron block. Most turbo models have an intercooled turbo (the exceptions being the single cam RB20ET & RB30ET engines), and most have a recirculating factory blow off valve (the exceptions being when fitted to Laurels and Cefiros) to reduce compressor surge when the throttle quickly closes. The Nissan RB Engine is derived from the six cylinder Nissan L20A engine which has the same bore and stroke as the RB20. All RB engines were made in Yokohama, Japan where the new VR38DETT is now made. Some RB engines were rebuilt by Nissan's NISMO division at the Omori Factory in Tokyo as well. All Z-Tune Skylines were completely rebuilt at the Omori Factory.

Bore and stroke

All Nissan engines follow a naming convention, identifying the engine family (in this case, RB), displacement, features present—see the list of Nissan engines for details.
The stock dimensions for the Nissan RB Engine

• RB20 - 2.0 L (1998 cc, bore: 78.0 mm, stroke: 69.7 mm)
• RB24 - 2.4 L (2428 cc, bore: 86.0 mm, stroke: 69.7 mm)
• RB25 - 2.5 L (2498 cc, bore: 86.0 mm, stroke: 71.7 mm)
• RB26 - 2.6 L (2568 cc, bore: 86.0 mm, stroke: 73.7 mm)
• RB30 - 3.0 L (2962 cc, bore: 86.0 mm, stroke: 85.0 mm)
• "D" indicates a dual overhead cam as opposed to a single overhead cam
• "E" indicates the individual engine ports are electronically fuel-injected
• "S" indicates the engine is carbureted
• "T" indicates the engine has a factory installed turbocharger
• "TT" indicates the engine has factory installed twin turbochargers
• "P" indicates the engine runs on LPG (liquefied petroleum gas)

RB20

RB20ET engine in an R31 Passage Wagon

There were a variety of 2.0 L RB20 engines produced:

• RB20E - single-cam (96 to 110 kW (130 to 145 ps) @ 5600 rpm, 167 to 181 N·m (17 to 18,5 kgf·m) @ 4400 rpm)
• RB20ET - single-cam turbocharged (125 kW (170 PS) @ 6000 rpm, 206 N·m (21.0 kgf·m) @ 3200 rpm)
• RB20DE - twin-cam (110 to 114 kW (150 to 155 PS) @ 6400 rpm, 181 to 186 N·m (18.5 to 19 kgf·m) @ 5600
• RB20DET - twin-cam turbocharged (158 kW (211 PS) @ 6400 264 N·m (27.0 kgf·m) @ 3200 rpm)
• RB20P - single-cam (94 PS @5600 rpm and 142 N·m @2400 rpm)
• RB20DET-R - twin-cam turbocharged (210 ps at 6400 rpm and 245 N·m at 4800 rpm
• RB20DE NEO - twin-cam 155 PS, improved low end torque, reduced fuel consumption and emissions.

RB20DET swap into a Nissan 240SX

The first RB20ET/DE/DET engines were fitted to the HR31 Skyline and the Nissan Fairlady 200ZR (Z31 chassis), produced from August 1985. The early twin cam engines featured the NICS (Nissan Induction Control System) injection system, while the later twin cam engines used ECCS (Electronic Concentrated Control System). Later versions which used ECCS engine management, discarded the twelve tiny runners for six much larger ones (though they retained twelve ports on the head, so there was a splitter plate). It was also fitted to the A31 Cefiro, C32 and C33 Laurel. The Fairlady 200ZR was fitted with an intercooled NICS type RB20DET.
The first RB20E engine was used in the C32 Laurel, produced from October 1984.
Laurels, R32 Skyline and Cefiros used the second (1989–1993) series RB20E/DE/DET. This had an improved head design, and used the ECCS injection system. These later motors are known as 'Silver Top' engines.
RB20DE Camshaft duration 232° in, 240° ex lift: 7.3mm in, 7.8mm ex
RB20DET Camshaft duration 240°in, 240°ex lift: 7.3mm in, 7.8mm ex
RB20DET Red top Camshaft duration 248°in, 240°ex lift: 7.8mm in, 7.8mm ex
RB20DE NEO Camshaft duration and lift are yet to be added
The 210 PS RB20DET-R was used in the Nissan Skyline 2000GTS-R (HR31) and was limited to 800 units.
The RB20P is the autogas LPG (Liquefied petroleum gas) version of the RB20, but with 12 valves (OHC).

RB24S

Nissan RB24S engine, Carburetor, SOHC, used in the Latin American market Laurel Altima A31 (an export market name for the A31 Cefiro)

This is a very rare engine, as it was not produced for the Japanese domestic market. These were fitted to some left hand drive Nissan Cefiros exported from Japan new. Mechanically, the RB24S combines an RB30E head, RB25DE/DET block and RB20DE/DET crank with 34 mm height pistons. The resulting 86.0 mm bore and 69.7 mm stroke combined to form a 2,428 cc inline-six engine.
This engine used carburetors instead of the Nissan ECCS fuel injection system. It is able to rev higher than the RB25DE/DET (as it has the same stroke as the RB20DE/DET) as well as being almost the same displacement as the RB25DE/DET. A common modification is to fit a twin cam head from other RB series motors while retaining the carburetor set-up. The standard single cam form produced 141 PS at 5,000 rpm and 20.1  kgf·m (197 N·m) of torque at 3,000 rpm.

RB25

1993 RB25DET with VCT (NVCS)

1998 NEO RB25DET

The 2.5 L RB25 engine was produced in four forms:

• RB25DE - NON-TURBO twin-cam 140 kW/190 PS (180 - 200 hp ) @ 6000 rpm, 255 N·m (26.0 kgf·m) @ 4000 rpm)
• RB25DET - twin-cam TURBO (T3 Turbo) (245 to 250 hp and 319 N·m)
• RB25DE NEO- NON-TURBO twin-cam 147 kW/200 PS @ 6000 rpm, 255 N·m (26.0 kgf·m) @ 4000 rpm)
• RB25DET NEO - twin-cam TURBO (206 kW (280 PS) @ 6400 rpm, 362 N·m (37.0 kgf·m) @ 3200 rpm)

RB25DE and DET engines produced from August 1993 also featured NVCS (Nissan Variable Cam System) for the intake cam. This gave the new RB25DE more power and torque at lower rpm than the previous model. From 1995,(Series 2 Engines) both the RB25DE and RB25DET had a revised electrical system and the turbocharger on the RB25DET(S2) had a ceramic compressor wheel rather than aluminium. The most obvious change to the system was the introduction of ignition coils with built in ignitors, therefore the coil ignitor that was on previous models was not used. Other changes were, different air flow meter, engine ECU, cam angle sensor and throttle position sensor. Mechanically Series 1 and Series 2 are very similar, the only mechanical difference would be the camshafts as the Series 2 Cam Angle Sensor's shaft that goes into the exhaust cam is slightly different. This is very important not to mistake. (early Series 2 featured the traditional Mitsubishi CAS which was later swapped for the Black CAS because of a positioning tooth which occasionally broke off)
In May 1998 a NEO head was fitted, which enabled the engine to be classified as a low emission vehicle (LEV) engine due to their lower fuel consumption and emission output. The NEO head featured solid lifters rather than hydraulic, revised camshafts, with on/off solenoid Variable VCT, used a hotter 82 °C thermostat, model-specific coil packs and a revised inlet manifold (the runner diameter is reduced from 50mm to 45mm to increase air velocity and low end torque) in particular the RB25DE NEO which had two inlets going into the inlet manifold. The combustion chamber of the head is smaller so GT-R spec connecting rods are used to compensate as well as model-specific pistons. The turbo received the larger OP6 turbine which some came with steel compressor and turbine wheels, where others had the nylon plastic compressor wheel and ceramic turbine wheel. Some also used an N1 type oil pump and had the oil pump drive collar on the crank revised to help cope with the breakage problems associated with fast, high revs. All in all they are quite a different engine in their own right - a culmination of 20 years of Nissan RB engine building rolled into one.
The non-VCT, non-turbo RB25DE was fitted to the R32 Skyline, the VCT turbo and non-turbo was fitted to R33 Skylines and the WNC34 Stagea. Early R34 Skylines use the non-NEO RB, later Skyline and Stagea (WGNC34) models use the NEO version.
R32 Skyline RB25DE Camshaft duration 240°in, 232°ex lift: 7.8 mm in, 7.3 mm ex
R33 Skyline RB25DE Camshaft duration 240°in, 240°ex lift: 7.8 mm in, 7.8 mm ex
RB25DET Camshaft duration 240°in, 240°ex lift: 7.8 mm in, 7.8 mm ex
RB25DE NEO Camshaft duration 236°in, 232°ex lift: 8.4 mm in, 6.9 mm ex
RB25DET NEO Camshaft duration 236°in, 232°ex lift: 8.4 mm in, 8.7 mm ex

RB26DETT

RB26DETT from an R34 GT-R.

The RB26DETT engine is a 2.6 L Inline-6 engine manufactured by Nissan, for use in the 1989-2002 Nissan Skyline GT-R. The RB26DETT engine block is made from cast iron, while the cylinder head is made from aluminium. The cylinder head contains 24 valves (4 valves per cylinder), and uses a dual overhead camshaft setup. The intake of the RB26DETT varies from other RB-series motors in that it has six individual throttle bodies (3 sets of 2 throttle assemblies that are siamesed together) instead of a single throttle body. The engine also uses a parallel twin-turbo system, using a pair of T25-type ceramic turbochargers set by the wastegates to limit boost pressure to 10 psi, although the Skyline GT-R has a built in boost restrictor to keep boost under 14 psi.

This Nissan RB26DETT engine is on display at the Nissan Engine Museum in Yokohama, Japan.

This Nissan RB26DETT engine is on display at the Nissan Engine Museum in Yokohama, Japan.

This Nissan RB26DETT engine is on display at the Nissan Engine Museum in Yokohama, Japan.

The first 2.6 L RB26DETT was rated by Nissan at around 276 HP (206 kW) @ 6800 rpm and 260 lb·ft (353 Nm) @ 4400 rpm. By the end of production, power levels had gone up to around 276 HP (206 kW) @ 6800 rpm and 289 lb·ft (392 Nm) @ 4400 rpm, not only because of developments and modifications to the engine, but also because of the "Gentlemen's Agreement" made between Japanese automakers to limit the "advertised" horsepower of any vehicle to 280 PS (276 HP). The RB26 is widely known and became quite popular for its strength and power potential, making it a modification friendly platform for tuners and aftermarket modifications in general, not unlike Toyota's 1JZ-GTE engine. It is common for modified engines to achieve outputs of 500 hp+. Some of the most extreme and extensive modifications done to the RB26 have resulted in figures of 1000 hp+, even up to 1,638 hp.^[1][2]

	Duration		Lift
Camshaft	Intake	Exhaust	Intake	Exhaust
RB26DETT	240°	236°	8.58 mm	8.28 mm
RB26DETT N1	240°	236°	8.58 mm	8.28 mm

Some factory features of the RB26DETT:

• 6 throttle body intake
• Solid lifter valve actuation, bucket on shim
• Belt driven cams
• CAS (crank angle sensor) driven off exhaust cam, tells ECU (engine control unit) crank/cam position
• water cooled, oil pressure lubed turbos
• OEM cast pistons have cooling channels under the crowns (extra oil cooling to keep piston temperatures down)
• Piston oil squirters
• Sodium filled exhaust valves
• 8 Counter weighted crankshaft
• 'I' beam con rods (more reliable with ARP rod bolts fitted)

There is a common oiling problem with the pre-1992 R32 RB26 motors, as the surface where the crankshaft meets the oil pump was machined too small, eventually leading to oil pump failure at high rpm. This issue was resolved in later versions of the RB26 with a wider oil pump drive. Aftermarket performance parts makers also make oil pump extension drive collars to rectify this problem. More recently a spline drive solution has been developed by an aftermarket tuner Supertec Racing who moves away from the OEM flat drive system and uses splines to drive the oil pump gears in the same way as Toyota's 1JZ GTE engine as found in the Supra MKIV. This kit is available for most uprated RB26 oil pumps including Nissans own OEM, N1 and Nismo.
Besides minor cosmetic updates and ECU fine tunings, changes were made in the R34 generation to ball bearing T28 turbochargers as opposed to journal bearing turbos. The R34 GT-R turbos retained the ceramic exhaust turbine wheel. Models that had steel exhaust turbine wheels included the R32 nismo, R32-R33-R34 N1 models and R34 Nür spec skyline GT-R's.
R34 GT-R model RB26DETT engine specific differences to the R32-R33 engines include:

• Candy red cam/coil pack covers
• Different coil cover emblem
• Plastic CAM gear cover
• Non painted inlet plenum (apparently also a lighter casting)
• Hitachi CAS (Crank angle sensor) has different drive fitting compared to earlier R32-R33 exhaust cams
• Igniter built into coil packs (no igniter pack on the rear of coil cover)
• Ball bearing turbo's with ceramic exhaust turbine wheels
• Stainless steel dump pipes
• Sump has a different ratio front diff (3:55)
• Different diameter coolant/heater pipes on intake side of block
• Dual mass flywheel

Originally the R32 GT-R was planned to have a 2.4L RB24DETT, and compete in the 4000cc class (in Group A rules, the displacement is multiplied by 1.7 if the engine is turbocharged). This was when Nismo was going through the process of designing the R32 GT-R to be a Group A race car. But when the engineers added the AWD system, they found it made the car heavier than expected and as a result, much less competitive. Nismo made the decision to make the engine a 2.6L twin turbo, and compete in the higher 4500cc class, resulting in the RB26DETT known today.^[3]
The RB26DETT was used in the following cars:

• Nissan Skyline GT-R BNR32
• Nissan Skyline GT-R BCNR33
• Nissan Skyline GT-R BNR34
• Nissan Skyline Autech GTS-4 ENR33 GTS-4 Chassis and naturally aspirated RB26DE used
• Nissan Stagea 260RS WGNC34改 (RS4 Chassis used)

RB26DETT N1

The RB26DETT N1 is a modified version of the RB26DETT engine, developed by Nismo (Nissan Motorsports) for Group A and Group N motorsport. Nismo found that the standard RB26DETT engine required too much maintenance for use in a Group-A or Group-N race car and subsequently designed the N1 block. This was first used in Bathurst Australia. Nismo balanced the crankshaft to a higher specification than stock, as the RB26DETT engine experiences vibrations between 7000 and 8000 rpm. The engine also received improved water and oil channels within the engine block. The pistons and top piston rings were also upgraded to 1.2 mm. The N1 engine also has upgraded camshafts and upgraded turbochargers.
Although all versions of the RB26DETT N1 engine use Garrett T25 turbochargers, the specification of the turbochargers changed through the 3 generations of the RB26DETT N1 engine (R32, R33, and R34). The R32, and R33 versions used Journal Bearing T25 Turbochargers. The R34 RB26DETT N1 engine used Garrett GT25 turbo chargers (which use a set of ball bearings).
The biggest difference between the turbochargers used in the N1 engine, and the standard RB26DETT engine, is that the turbine wheels in the turbocharger are made from steel, rather than the ceramic used for the standard RB26DETT turbochargers. The ceramic turbine wheels are found to be very unreliable when used at high rotational speeds inducing higher centrifugal forces (such as when the turbochargers are used at a higher boost pressure than stock). With the advances in manufacturing technology such as sealing and material processes. The N1 engine is theoretically said that when fuel and boost levels are modified, it is able to produce (and handle) in excess of 800 bhp without any modification to the engine block or rotating assembly.
The Nismo RB26DETT N1 engine block uses an 86 mm bore which can be bored up to either 87 mm or 88 mm. The N1 block is casted with an identification mark of 24U, whereas the standard RB26DETT block is marked with 05U. The RB26DETT N1 block is compatible with all GT-R engine bays.

RB28DETT

This is the engine used in the Nissan Skyline GT-R Z-Tune built by Nismo. It uses the stronger RB26 GT500 block (stamped with RRR), modified with Nich produces 510 bhp (368 kW) and 540 N·m of torque.^[4]

RB30

Four models of 3.0 L RB30 were produced from 1985 - 1991:

• RB30S GQ Patrol - carburetted single-cam 100 kW at 4,800 rpm, 224 nm at 3000 rpm
• RB30E VL Commodore - fuel-injected single-cam (114 kW (153 hp) at 5,200 rpm, 247 N·m (25.2 kgf·m) at 3,600 rpm)
• RB30E R31 Skyline - fuel-injected single-cam (117 kW (157 hp) at 5,200 rpm, 252 N·m (25.2 kgf·m) at 3,600 rpm)
• RB30ET VL Commodore - fuel-injected single-cam turbo (150 kW (201 hp) at 5,600 rpm, 296 N·m at 3,200 rpm)

This motor was produced for use in the Skylines, Patrols and rights bought by Holden because the Holden 202 (3.3 L) powering the Holden Commodore could no longer satisfy tightening emissions requirements, and with all new cars required to run on unleaded petrol by 1986 a quick replacement was needed. Nissan Motor Co. sold the RB30E to Holden for the VL Commodore. Because the radiator is fitted lower in relation to the engine in the VL, there is an increased likelihood of air locks forming in the (alloy) cylinder head, causing this to overheat and warp. This was less likely in the R31 Skyline as the radiator is mounted higher.^[5] The engine proved to be very reliable apart from this issue. The RB30S was found in some Middle Eastern R31 Skylines and in some Nissan Patrols. The RB30E was found in R31 Skylines and VL Commodores in Australia as well as in South African R31 Skylines (with 126 kW at 5,000 rpm and 260 Nm at 3,500 rpm)
The turbocharged RB30ET (producing 150 kW) was found only in the VL Commodore and consisted of a lower compression RB30E bottom end, more powerful oil pump, T3 Garrett turbocharger, 250 cc injectors and a different intake manifold. The motor itself is still popular today in Australian and New Zealand motorsport and drag racing in VL Commodores, R31 Skylines and swaps in other vehicles
Nissan Special Vehicles Division Australia produced two limited models of R31 Skylines, the GTS1 and GTS2. These contained slightly more powerful RB30E engines, containing longer opening duration cams and better flowing exhausts.

• GTS1 RB30E - injected single-cam (130 kW (174 hp) at 5,500 rpm, 255 Nm (26.0 kgf·m) at 3,500 rpm) - special cam profile, special exhaust^[6]
• GTS2 RB30E - injected single-cam (140 kW (188 hp) at 5,600 rpm, 270 N·m (27.5 kgf·m) at 4,400 rpm) - special cam profile, special exhaust, piggy back computer, valve porting^[7]

RB30DE

These rare engines were used in the Tommy Kaira M30 based on the R31 Skyline GTS-R. A modified RB20DE head was bolted onto the RB30E block. It delivered 177 kW (240 PS/236 hp) @ 7000 rpm and 294 N·m (30.0 kgf·m/216.9 lb.ft) @ 4800 rpm.

RB30DET

RB30DET - R31 RB30E block, R32 RB25DE head.

Nissan did not produce this engine. It refers to a turbocharged engine using an RB30E short block with the twin-cam head installed from another RB series engine. A common hybrid in Australia and New Zealand (referred to as the RB25/30 or RB26/30) uses an RB30E bottom end mated to a RB25DE,RB25DET or RB26DETT cylinder head and turbo (RB20DE and DET heads are not used as the bores are different in size; RB30 86.0 mm RB20 78.0 mm but were originally modified and used on the Tommy Kaira RB30DE as the RB25 engine did not exist). The RB25DE cylinder head from the A31 Cefiro C33 Laurel or R32 skyline (aka: Non VCT) can be used. The RB25DET (from the R33 Skyline or C34 Laurel or Stagea) head is also used, however an external oil feed must be fabricated for the variable cam timing (VCT) on the RB25DET, and the oil galleries at the front of the engine are misaligned. The variable cam timing may be disconnected altogether. It may be necessary to reduce the size of the oil restrictors in the block and machine a full face oil pump drive collar onto the crank, (to prevent it shattering at high RPM), with the use of a twin cam oil pump.
The fitment of a twin cam head from any of these engines onto a standard compression RB30E bottom end gives an ideal compression ratio, (around 8.2:1), for a mild to moderately modified street turbo engine, making the conversion popular amongst those who would otherwise convert their RB30E to a high compression RB30ET using original ET bolt on externals.
Although it has a larger displacement than the RB26DETT, maximum possible horsepower is less, as the RB30 block lacks the RB26 block's internal bracing, and consequently cannot rev as high due to harmonic issues at ~7500 rpm. To compensate, the RB30DET produces more torque at lower revs due to its longer stroke. However they have been known to reach engine speeds up to 11,000 rpm with extensive balancing and blueprinting.
There is also an 'RB30DETT' kit manufactured by OS Giken of Japan, which bolts an extension on top of the RB26 engine block, and fits liners, to give an 86 mm bore x 86 mm stroke. It is available as an assembled short block, containing billet chrome-molybdenum crank, billet chrome-molybdenum H-beam connecting rods, forged pistons, and costs ¥1,500,000.^[8]

RB-X GT2 & RB28DET

The RB-X GT2 (designed and built by REINIK) is an engine specially made for the NISMO 400R. The difference between this engine and a RB26DETT is that the engine is bored and stroked (87.0 × 77.7 mm) which results in 2771 cc. Engine produces 450 PS (331 kW or 443 HP) at 6800 rpm and 47.8 kgf·m (469 N·m or 347 lb·ft) at 4400 rpm.^[9]
This engine was manufactured with a reinforced cylinder block and cylinder head, metal head gasket, pistons with cooling channels, forged crank shaft, forged connecting rods, N1 turbine with reinforced actuator, high flow air cleaner, stainless down pipe, and low air resistance sport catalyzer, most of which were not offered for the RB26DETT. RB-X GT2 engines competed in LeMans 24hr race, Pikes Peak, and other forms of motorsports. GT500 and Z-tune engines are also based on REINIK's design although later built by NISMO's Omori Factory.
REINIK also made over 20 RB28DET based on the R33 RB25DET. These engines were ordered by Prince Nissan Dealership network for a special edition R33 GT25t called 280 Type-MR. The engine was built for high torque and limited to 300 PS (295 hp) and 261 lb.ft of torque.

Stroker Kits

There are many stroker kits available for RB Engines (some only available as proper kits while others being achievable by using cranks from other engines, for example a GT-R crank, pistons and rods in an RB25DET will make its displacement 2.6L as the Bore is the same as an RB26DETT).
Achievable Stroker Displacements for RB Engines:

• RB20 - 2.2, 2.4
• RB25 - 2.6, 2.7, 2.8
• RB26 - 2.7, 2.8, 2.9, 3.0, 3.15
• RB30 - 3.2 (Nitto), 3.3 (RIPS), 3.4 (Spool Imports)