Nissan engines

Nissan Motors uses a straightforward method of naming their automobile engines. The first few letters identify the engine family. The next digits are the displacement in deciliters. The following letters identify features added and are order specific based on the type of feature.

The features/letters follow a specific order and not all features are necessarily listed all of the time. The basic, common features follow this general order:

[Engine family character(s)] [two-digit engine displacement in deciliters] [1] [2] [3] [4] [5]

1 = Camshaft
2 = Fuel delivery
3 = Power adder
4 = 2nd power adder
5 = Special

A good example to start with is the Nissan VG30DETT engine. It belongs to the VG engine family, displaces 30 deciliters (3.0 liters), and the feature letters describe an engine with dual overhead camshafts, electronic port fuel injection and two turbo chargers.

The next example is the Nissan VQ35DE engine. It belongs to the VQ engine family and displaces 35 deciliters (3.5 liters). The feature letters describe an engine with dual overhead camshafts and electronic port fuel injection but leaves off any power adder descriptors because it is a naturally aspirated engine. The (single) turbocharged version of the VQ displaces 30 deciliters (3.0 liters) and is logically called the VQ30DET.

Not all features are necessarily described in the name. For example, the SR20VE engine has dual overhead camshafts but the variable valve lift design of the camshafts takes precedence in the naming scheme even though the "V" feature designation doesn't necessarily describe a DOHC arrangement. Many standard DOHC Nissan engines featured Variable Valve Timing, such as the VG30DETT, and as such do not use the "V" designation. "V" designation is only if the engine has variable valve lift.

A good example of an engine where not all of the feature designation spots are used is the L28ET engine. The two features listed being electronic port fuel injection designated with the "E" and the presence of a turbocharger designed with the letter "T". The engine has a single overhead camshaft so there is no "D" listed in the name; the camshaft type designation place being left out completely. Nissan does not have a letter designation for the SOHC configuration so the camshaft configuration type is assumed as SOHC if no letter is present.

Lastly, the MR16DDT engine has feature designations that describe an engine with dual overhead camshafts, direct cylinder fuel injection and a single turbocharger.

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