But every engine is built from the same simple, efficient design. The SUBARU BOXER, however, was originally designed with rigidity in mind, allowing the 92.0 mm x 75.0 mm bore and stroke of the 2.0-litre petrol four-cylinder engine to be changed to … This means two things;Good rotational balance means lower levels of vibration and harshness, which translates into less wear and tear and therefore higher levels of durability meaning a more reliable and lower cost of ownership.Because the crankshaft is sandwiched between two very rigid crankcase halves it is very well supported and therefore its durability is significantly enhanced and because it absorbs less vibration its design can be of a much lighter construction. This very important difference provides the key benefits of the horizontally-opposed (Boxer) engine layout where half of the total number of cylinders and therefore pistons lay on their sides in an east-west configuration moving in opposite directions.The key benefit of the Subaru 'Boxer' engine's horizontally-opposed layout is not about its power output or environmental performance but its contribution to the vehicle's handling, stability and as a result,Firstly, because the cylinders in the Boxer engine lay on their sides the overall height of the engine is significantly lower especially when compared to the more normal 'inline' engine where all the pistons move in the same direction in a north-south configuration. With these features, Subaru vehicles enjoy fundamentally more responsive, safer and more stable handling, faster maneuverability and better cornering.The ultra-low center of gravity improves cornering stability, contributing to more comfortable ride handling, more responsive handling and better avoidance capabilities.This type of engine is compact, lightweight and symmetrically positioned and low in the chassis, to ensure a more fluid and direct power output.The pistons move side by side, a configuration better balanced by nature, so they induce less vibration, generate better performance and reduce the wear of moving parts.Please consider supporting us by disabling your ad blockerSubaru Recalls 640K Vehicles for Issue That Can Increase Risk of CrashA Strong Mother Wins a $35K Subaru by Standing for 75 Hours Given the minimal time that is available in a relatively high revving engine on each cycle to completely burn all of the fuel, if the bore size becomes too large the flame travel time from the spark plug to the outside of the cylinder wall becomes problematic. However the larger width of flat engines (compared with the more common inline and V layouts) is a drawback, particularly when the engine is located between the steered wheels. This meant difficulty in accommodating the wider engine within the chassis without making the overall width of the car greater, which is not desirable from a packaging point of view and given our traffic and road conditions.When an engine becomes 'over square' meaning the bore is greater than the stroke, the efficiency of combustion becomes increasingly difficult. This was because any increase in the length of the cylinder (stroke) would make the overall engine width greater. Subaru first utilized a boxer engine in 1966 in the Subaru 1000. The Subaru WRX STI is a prime example of the capabilities of a boxer engine.

In addition, the engine is aligned in the axis of the drive system, to ensure optimal transfer of power. Learn More Due to its low height, the 'Boxer' engine can be redirected under the floor of the passenger compartment avoiding any penetration of the passenger compartment and therefore reducing the chance of front occupant injury.What are the negative aspects of the 'Boxer' horizontally opposed engine design? SUBARU BOXER ® Engine Options. This also makes a very significant contribution to vehicle balance, stability and handling particularly when cornering or making rapid changes of direction.The overall length of the Subaru Boxer engine is comparatively short compared to a conventional 'in line' or 'V' engine layout as a result of the degree of cylinder overlap that is possible due to the opposed piston configuration. According to … The SUBARU BOXER engine, which powers all Subaru vehicles, is known for its excellent balance, smooth ride, and superior power delivery – for almost 50 years. The horizontally opposed cylinder configuration provides a low center of gravity, which contributes to balanced handling, cornering, and stability, regardless of the type of pavement.Subaru offers a range of variations of this engine – four or six-cylinder, atmospheric or supercharged – suitable for various driving styles and drivers.