How does the Subaru boxer engine work

Subaru boxer engine

The boxer engine era began with the VW Beetle, for a while Ferrari and Alfa Romeo built boxer engines. Currently only Porsche, BMW for motorcycles and Subaru (since 1966) produce boxer engines.

In this construction with horizontally opposed cylinders, the inertial forces balance each other out. This causes the engine to run with little vibration, without any balance shafts. In addition, the engine has a low overall height, which keeps the center of gravity of the vehicle low.

Thanks to the good mass balance of the boxer engine, larger-volume engines with four cylinders can be implemented without losing running smoothness, for example the 2.5 liter engine in the outback. The advantage of fewer cylinders with the same displacement is that there is less friction in the four-cylinder engine and less mass and fewer components have to be moved.

As a result, the engine works with less loss, which means more power and lower consumption. This is a simple explanation, which of course can be complicated as desired, which we will dispense with at this point. It is also worth mentioning that all Subaru are satisfied with regular gasoline (95 octane). Sensors determine the fuel quality and adjust the engine management accordingly.

With the 2013 model year, modified engines were used, with various technical changes. All engines now have, among other things, a maintenance-free timing chain instead of a toothed belt (connection of crankshaft and camshaft to control the valves). The timing belt has to be changed (e.g. every 120,000 km), which in some competing models has a significant 4-digit amount (up to CHF 3,000 according to the K-Tipp workshop costs survey).

The performance of the new engines remained the same, but they consume significantly less.