FROM J.D. POWER: When it
FROM J.D. POWER: When it comes to internal combustion engines (ICE), the vast majority of the cars sold are motivated by “inline” and “V-type” engines. These terms designate the configuration of the cylinders arranged along the crankshaft.
Inline engines typically have three, four, or six cylinders lined up in a vertical row. V-type engines angle the cylinders in a shape similar to the letter V, alternating cylinders on either side of the crankshaft. They typically have six, eight, ten, or twelve cylinders.
Far less common are HORIZONTALLY OPPOSED engines, which usually arrange four or six cylinders horizontally in relation to the crankshaft. This is why they are often called flat-4 or flat-6 engines. Alternatively, because the pistons within these cylinders “jab” outward from the crankshaft, they are known as BOXERr ENGINES.
Currently, the boxer engine is a defining trait of the Subaru brand. From the BRZ sports car to the Ascent family-sized SUV, every vehicle in its lineup has a flat-4 with or without turbocharging. Until a few years ago, some Subarus also had a flat-6 engine.
AND, FROM AUTOS.CA:
Only two manufacturers currently use horizontally opposed engines: Subaru and Porsche. Subaru uses four and six-cylinder versions; Porsche uses a six-cylinder version in its Boxster, Cayman and Carrera models, but V6 and V8 engines in other models.