NISSAN RB ENGINES

The RB engine is a 2.0L to 3.0L straight-6 four-stroke gasoline engine from Nissan.

Both SOHC and DOHC versions have an aluminum head. The SOHC versions have 2 valves per cylinder and the DOHC versions have 4 valves per cylinder, all cam lobes move only one valve. All RB engines have belt driven cams and a cast iron block. All turbo models have an intercooled turbo (except the single cam RB20ET & RB30ET engines), and most have a recirculating factory blow off valve (except when fitted to Laurels and Cefiros) to reduce boost surge when the throttle is closed.

Some sources indicate the 'RB' name stands for 'Race Bred', although this is disputed. The Nissan RB Engine is derived from the 6 cylinder Nissan L20A engine which has the same bore and stroke.

All Nissan engines follow a naming convention, identifying the engine family (in this case, RB), displacement, and features present- see the list of Nissan engines for detail.

The stock dimensions for the RB engines;

• 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 (2982 cc, bore: 86.0 mm, stroke: 85.0 mm)
• "D" indicates a double overhead cam as opposed to a single overhead cam
• "E" indicates the engine is electronically fuel-injected as opposed to carbureted
• "T" indicates the engine has a factory installed turbocharger
• "TT" indicates the engine has a factory twin turbocharger

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