Production Of The Subaru Fb20 Boxer Engine

The FB has an all new block and head featuring dual overhead cams with intake and exhaust variable valve timing (AVCS – Active Valve Control System), and a timing chain that replaced the timing belt. Moving to chain-driven cams is said to allow the valves to be placed at a more narrow angle to each other and shrink the bore of cylinder from 99.5 mm to 94. It results in less unburned fuel during cold start, thereby reducing emissions. Subaru is able to maintain the exterior dimension substantially unchanged by asymmetrical connecting rods like those in EZ36. The FB is only marginally heavier. In Jan 2011, Car and Driver was told direct injection would be added soon.