FHI DEVELOPS NEW-GENERATION SUBARU BOXER ENGINE

New horizontally-opposed engine provides superior combination of environmental friendliness and enjoyable driving

TORONTO, Nov. 4 /CNW/ - Fuji Heavy Industries Ltd. (FHI), the parent company of Subaru Canada, Inc. (SCI) has announced the launch of a new-generation Subaru Boxer engine that combines the technology and know-how used in horizontally-opposed boxer engines, the core technology that has supported Subaru's unique driving since it was first employed in the Subaru 1000 in 1966. This overall renewal is the first in 21 years, since the second-generation boxer engine was introduced in the first Legacy models in 1989.

This third-generation horizontally-opposed 4-cylinder gasoline engine showcases Subaru's latest engineering research and development, and a new level of performance demonstrates Subaru's unique expertise in Boxer engine technology. The engine was entirely renewed, starting from the basic structure, while all the advantages of the horizontally-opposed layout were maintained: light weight, compactness, low centre of gravity, and superior balance to minimize vibration.

Third-generation improvements include advances in both environmental friendliness as well as driving performance: the new engine is more fuel efficient, while offering smooth, muscular acceleration in all speed ranges. Subaru engineer so designed the engine specifically so that future developments and upgrades could be seamlessly integrated.

FHI has built a new factory at its Gunma Oizumi plant exclusively for the production of this new-generation boxer engine. This new plant offers state-of-the-art production facilities that make full use of Subaru's engine manufacturing know-how, as well as a highly efficient production system able to deliver products that meet highest standards of quality.

Major Features of the New-Generation Subaru Boxer

In the re-design of this engine, every structure and operation were examined for opportunities to improve operation.

The bore and stroke, the basic structure of any engine, have been reviewed to achieve a compact combustion chamber. The pistons have also been re-designed for a longer stroke, to allow high combustion efficiency and generate effective mid-low speed torque with improved fuel efficiency.

Fuel efficiency has been further improved through optimization of the intake port configuration and the addition of partitions inside the ports, the use of tumble generating valves (TGV), and the use of an exhaust gas recirculation (EGR) cooler. AVCS, Subaru's Active Valve Control System, is used on intake valves for improved engine breathing. The use of lightweight primary moving parts, such as pistons and connecting rods, and a highly efficient and compact oil pump provides an approximately 30 percent reduction in friction loss and further improves fuel efficiency and revolution response. Cooling has been optimized by using separate engine cooling circuitry for the block and the head, resulting in improvements to fuel efficiency and output.

Engine Outline

	New Boxer engine	Previous engine
Engine type	Horizontally-Opposed 4 cylinder DOHC	Horizontally-Opposed 4 cylinder SOHC
Displacement	2.5-litre	2.5-litre
Compression ratio	10.5	10.2
Bore x Stroke	94 x 90mm	99.5 x 79mm
Max. output	170 hp @ 5,800 rpm	170 hp @ 6,000 rpm
Max. torque	174 lb.-ft. @ 4,100 rpm	170 lb.-ft. @ 4,400 rpm

Major Changes and Results

Items	Output	Fuel efficiency	Exhaust emissions
Longer stroke	O	O	O
Compact combustion chamber	O	O	O
Lighter parts in moving parts		O
Cooled EGR system	O	O
Intake AVCS	O	O	O
TGV		O	O
Compact oil pump		O

Advantages of Horizontally-Opposed Engines

Kinematic performance: Compared to in-line engine and V-type engines, the height of the Subaru Boxer engine is a lower centre of gravity for the entire vehicle. The lightweight, compact design and symmetrical layout allow a smaller yaw moment of inertia.

Reduced vibration: The pistons on the left and right sides of the engine move in symmetrical opposition, cancelling out vibrations. This allows a smooth revolution with little detectable vibration.

Occupant protection: Since the engine sits low, strong forces from the front such as a head-on collision will drive the engine underneath the car. As a result, there is a reduced risk of the engine being forced into the cabin and injuring passengers. This engine placement also means there is ample space between the engine and the hood. This space will absorb some of the force in the event of a collision, reducing injury to pedestrians.

Subaru is fully committed to develop new products on the theme of integrating enjoyable and reliable driving with environmentally friendly solutions. This same theme applies to the new-generation boxer engine, which will be positioned as a main engine and the starting point of its future power unit strategy.

The first deployment of this new engine will be in the 2011 Forester in late 2010.

About Subaru Canada, Inc.
Subaru Canada, Inc. is a wholly owned subsidiary of Fuji Heavy Industries Ltd. of Japan. Headquartered in Mississauga, Ontario, the company markets and distributes Subaru vehicles, parts and accessories through a network of more than 85 authorized dealers across Canada.

For further information:

Elaine Griffin [phone]