Engine configuration

Piston engines are often categorized by their cylinder layout, valves and camshafts.

Gas turbine engines are often categorized into turbojets, turbofans, turboprops and turboshafts.

These engine banks use a single cylinder head so are technically a straight bank with the name "VR" coming from the combination of German words “Verkürzt” and “Reihenmotor” meaning “shortened inline engine”.

Rotary engines have a similar configuration, except that the crankshaft is fixed and the cylinders rotate around it.

An opposed-piston engine is similar to a flat engine in that pairs of pistons are co-axial but rather than sharing a crankshaft, instead share a single combustion chamber per pair of pistons.

One layout has a flat/boxer engine at its center and adds an additional opposed-piston to each end so there are two pistons per cylinder on each side.

A Delta engine has three (or its multiple) cylinders having opposing pistons, aligned in three separate planes or 'banks', so that they appear to be in a Δ when viewed along the axis of the main-shaft.

[4][5] Wankel engines can also be classified based on whether they are naturally aspirated or turbocharged.