An X engine is a four-cylinder or four-row single-shaft piston internal combustion engine. The cross-section of the X engine forms the shape of the letter X, hence the name.

An X engine is a special type of radial engine, but if it has only four cylinders, it is also a flat engine.

How was the X engine created?

The X engine was created by connecting two V engines or derived from them. This engine type uses only one crankshaft to which the pistons are attached using connecting rods, just like a radial engine.

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Radial engine: Did you know what type of motor it is?

Thus, one piston is connected to the crankshaft directly by the main connecting rod, which has a suspension eye. The connecting rods of the other pistons are attached to them using pins.

X engine construction

X engines are very rare mainly because they were heavier and more complicated than the star engines they replaced. With the same number of cylinders, the design of the X engine is more compact compared to the design of the V engine.

The crossover engine was used mainly during the Second World War, but today this type of engine is obsolete and not used. So most engines with X cylinders are from the Second World War period. These engines were designed to power larger military aircraft such as bombers. Also, most of the known crossover engines are twenty-four-cylinder.

Twenty-four-cylinder engine (X24)

The 24-cylinder engine (X24) is one of the few known X-type engine configurations to have been produced. This engine type was built from two V12 engines connected by a single crankshaft.

This engine design is lighter than the W or H engines that power aircraft but requires two crankshafts.

Conclusion

X engines were supposed to find their use in addition to airplanes under the hood of cars. Unfortunately, this never happened. Henry Ford originally planned it with his prototype X8 engine, which was eventually replaced by a V8 engine. Who knows, maybe we will see an X-engine deployment under a car's hood one day.