SUBARU
BOXER ENGINES

Find Top-Quality Subaru Boxer Engines

At SSI Subie Specialists, Inc, the most common rebuilds that we do are for the Legacy, Outback, Forester, and the Impreza. However, we can also rebuild engines for your B9 Tribeca and Crosstrek.

While every engine is different, we are the best shop in the country for rebuilding your Subaru boxer motor. Regardless of the year or model, we'll give you a genuine OEM Subaru spec motor.

What is a Boxer Engine?

Subaru is known for using boxer engines in all of its vehicles. You may ask, what is a boxer engine? It is an engine that has horizontally opposed pistons instead of the common v-shaped or inline engine. With the pistons aligned like this, it creates a more seamless and efficient engine. The opposing pistons actually balance one another out so there is less vibration, more fluid rotation, and enhanced efficiency. The boxer engine is perfectly symmetrical and has a low center of gravity, which creates for excellent handling around tight corners, better balance, and makes for a safer vehicle all-around.

Subaru FB Engines

The Subaru FB 4 cylinder Boxer engine replaced the former EJ 4 cylinder engine. This new model of engine found its way into the 2011 and newer Forester, 2012 and newer Impreza, and the 2013 and newer Legacy/Outbacks, as well as the Crosstrek. This new engine continues to utilize Subaru's signature horizontally-opposed boxer engine. So what is the major differences between these two types of engines?

The FB has an all new block and cylinder head design that features dual overhead cams with intake and exhaust variable valve timing and a timing chain replacing the older timing belt. The chain driven cams allow the valves to be placed at a narrower angle. This allows the FB engine to suck air in more quickly, and the elongated cylinder also results in less unburned fuel during cold starts. There also is a reduction in friction losses with lighter pistons and connecting rods. The connecting rods were redesigned to weigh less and are shaped to keep the engine the same width as the EJ while allowing a longer stroke. The FB engine has about a 10% better fuel economy than the previous EJ. It has the same horsepower and a slightly higher torque at a lower RPM.

SSI Subie Specialists remanufacture FB engines. We are ONE of the ONLY companies that will remanufacture the FB engine due to its complex design.