When you ask a car person what sound a loud Subaru makes, they’d likely mention the thrum of the brand’s iconic boxer four cylinder, since that’s the sound Subaru’s legendary rally cars make while screaming through a nordic forest. I recently came across a video of a straight piped flat six Subaru Legacy, and suddenly realized that it has a very similar pitch to that of a Porsche. Now I’m fantasizing about how badass a straight piped B9 Tribeca would be.
Horizontally opposed engines like those used in Subarus and in Porsche’s sports cars don’t sit in a straight line or V-shape like most engines on the market, the pistons move horizontally, or flat. This allows the mass of the engine to sit lower in the vehicle which contributes to a lower center of gravity, and the opposing forces of the pistons also gives flat engines an especially smooth character.
Why don’t more manufacturers use this engine configuration? Flat engines are very wide and take up a lot of space in the engine compartment. This significant width often means the engine compartment is very tight, which can make even simple maintenance tasks more challenging. They are also generally more complex than inline engines due to their wide-set nature. Porsche and Subaru have used this engine configuration for decades and devoted millions of dollars to developing them, so it makes sense that these companies stick with their unique engine design. It doesn’t, however, make much sense for an inexperienced manufacturer to suddenly switch away from an inline or V-shaped configuration and expend the time and energy necessary to develop a boxer engine.
Aside from the engineering challenges associated with boxer engines, they can sound pretty epic with the right exhaust, and this YouTuber has certainly found the right exhaust to turn this Subaru into a screamer. More Subaru fans need to start modding out H-6 Subies so the hills can be filled with the enchanting sounds of flat six greatness. Flat four Subarus still sound great, but I’m ready for Subaru’s flat six to get its moment in the spotlight.