The New Subaru FB20 Naturally Aspirated Engine
Original Translation from “Proud of Boxer. Technology and passion for Subaru Boxer Engine.”
FB20 has the following specifications
Engine Form: 4-Cylinder DOHC Flat Engine
Engine Type: FB20
Engine Displacement: 1995cc
Bore x Stroke: 84.0 x 90.0mm
Compression Ratio: 10.5
Maximum Output: 109kW/6000rpm
Maximum Torque: 196Nm/4200rpm
FB20 Versus EJ20
The Bore pitch remained at 113mm to keep room for the 2.5L version. The longer stroke improves the fuel Efficiency, and even with longer stroke, the engineers were able to maintain the new FB engine close to the dimension of EJ engine.
The new TGV (Tumble Generator Valve) on the FB20 has a new flap feature to adjust the air flow to the intake chamber. The FB20 also features an in-port fuel injection, a major change from the EJ predecessor. The fuel injectors are located on the cylinder heads to improve fuel efficiency and reduce gas emissions.
In-port injection
Breaking down the internals of FB20
The valve is direct bolt-on with cam angle at 410 with cam distance of 126mm on EJ engine.
FB20 uses roller rocker on the valve to retain the engine width and reduce friction loss. Valve cam angle is reduced to 270 and cam distance to
Smaller bore on FB20 engine
FB20 Cylinder head, separate pieces from the cam carriers, reducing the weight
FB20 Connecting rods shaped to engine width similar to the EJ. FB20 piston is smaller. The crown design is to maintain tumble flow’s momentum.
Tags: FB20, subaru, Subaru FB20
This entry was posted on Friday, March 11th, 2011 at 6:32 pm and is filed under News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.