Inlinefives

Inlinefives, also known as straight-five engines or I5 engines, are internal combustion engines with five cylinders arranged in a single straight line. These engines are a less common configuration than the more prevalent inline-four or V6 engines. Inlinefives offer a balance between the smoothness and power of a straight-six engine and the more compact size of an inline-four. The odd number of cylinders inherently creates an uneven firing order, which can lead to more vibration than an even-cylinder engine. To mitigate this, inline-five engines often employ balance shafts to counteract the primary and secondary vibrations.

The inline-five configuration typically achieves its displacement by having five cylinders of a specific bore and stroke. The exhaust gases from each cylinder are usually directed into a common manifold. Historically, inline-five engines have been utilized in a variety of vehicles, from passenger cars to trucks. Their relatively compact design for their displacement made them suitable for transverse (sideways) mounting in front-wheel-drive vehicles, a common layout in many modern cars. However, the inherent vibration characteristics and the complexity of balancing shafts have led some manufacturers to favor other engine configurations for new designs. Despite this, inline-five engines are still appreciated for their distinct engine note and their historical significance in certain automotive applications.