The Nissan L series of automobile engines ranged from 1.3 L to 2.8 L in both inline-four and inline-six configurations and were produced from 1967 through 1986. This was the engine of the Datsun 240Z sports car as well as the Datsun 510 and the first Nissan Maxima. These engines are known for their extreme reliability, durability, and parts interchangeability. It is a two-valves per cylinder SOHC non-crossflow engine, with an iron block and an aluminium head. The four-cylinder L series engines were replaced with the Z series and later the CA series, while the six-cylinder L series engines were replaced with the VG series and RB series.
L20B
The L20B was a 1,952 cc (85.0 x 86.0 mm) engine produced from 1974 through 1985. It produces 110 hp (82 kW) in 1974-75 form with 112 lb·ft (152 N·m) of torque as installed in the Datsun 610 and 97 hp (72 kW) in 1977-78 form with 102 lb·ft (138 N·m) of torque as installed in the 200SX.[1] The L20B engine introduced larger-diameter (60 mm) main bearings while retaining a fully counterweighted crankshaft. The U60 crankshaft also ushered in the use of a six-bolt flywheel boss. The block introduced a taller deck height to accommodate the longer stroke and connecting rods. This specification would also be used later in the Z20 and Z22 engine series. The bigger powerplant even helped spawn an important new offering from Datsun's competition department -50mm Solex twin-choke carburetor kits- complete fuel systems that help produce nearly double the power from the ubiquitous L20B. The legendary robustness, the nearly square configuration and the rod-to-stroke ratios possible have made this engine a popular choice among tuners for turbocharging.
The engine used a carburetor but switched to fuel injection (and round instead of square exhaust ports) in some non-USA markets in 1977. Carburetors were used in all US L20B applications for both cars and trucks. There were six versions of the L20B in the US- U60, U67, U95 (used in cars) and U60, U67, B98, 04W, and 05W (used in trucks). In the US, the L20B was used in six different model families -A10, 610, 710, S10, 620, and 720 models- making it the most versatile powerplant in the company's US history. To avoid confusion with the six-cylinder L20, Nissan called this engine the L20B and redesignated their six-cylinder engine L20A.
