[quik1987]

Some detail about the FB20 that might apply to the FA20:

Subaru FB engine

(Japanese: Subaru FB engine) New generation boxer engine announced on 23 September 2010.[6] The Subaru FB engine is entirely new as of 2010. Subaru aims to reduce emission and improve fuel economy. The key is to increase and broaden torque output. Subaru increases the stroke but decreased the bore.
The FB has an all new block and head. It now has DOHC, with intake and exhaust variable valve timing (AVCS - Active Valve Control System), and timing chain that replaced the timing belt. Moving to chain-driven cams is said to allow the valves to be placed at a narrower angle to each other and shrink the bore of cylinder from 99.5 mm to 94. It results in less unburned fuel during cold starts, thereby reducing emission. Subaru is able to maintain the exterior dimension substantially unchanged by asymmetrical connecting rods like those in EZ36. The FB is only marginally heavier. Car and Driver is told direct injection will be added soon. Subaru claims a 28-percent reduction in friction losses, mainly due to lighter pistons and connecting rods.[7][8] The FB has a 10% increase in gas mileage with the power coming on sooner and the torque band being broader.

• FB20: 1,995 cc, DOHC, 84mm bore x 90mm stroke, 10.5:1 Compression Ratio,

Rated at: 109 kW (148PS) @6,000 rpm, 196 Nm (20 kgm) @4,200 rpm in (2011+ JDM Subaru Forester)[9],Rated at: 145 hp, 145 ft-lb (2012+ Subaru Impreza)