Considered a stunning automotive achievement, Subaru managed to convert its popular streamlined boxer engine into a fuel efficient diesel powerhouse. There was some challenges presented in the task, but when all was said and done, Subaru came out with the first ever horizontally opposed diesel engine created for passenger cars.
Though initially Subaru did not intend on releasing this unique engine design to American Subaru consumers, it appears that America's ever increasing crisis with gas gouging oil execs forced them to rethink their strategy in order to ease the American Subaru owner's mind. This led to the announcement by Fuji Heavy Industries (Subaru parent company) president Ikuo Mori that the new diesel engine should be available stateside by the year 2010.
The numbers are somewhat astonishing, as 'diesel engine' is usually synonymous with 'gas guzzler'. Yet Subaru has produced a diesel engine light enough to provide about 50 mpg on the open highway and about 30 mpg in city. It's a four-cylinder, 2.0 which can produce 148 hp and 258 pounds of torque with 1,800 rpm's. It runs on a five-speed transmission.
Part of the boxer's lightness comes from the fact that it is made of a rigidly formed, all aluminum engine block, as are the cylinders. In order to provide fewer emissions, the turbocharger is mounted directly beneath the engine block and connected to the catalytic converter. This also helps the vehicle's center of gravity.
It is also much quieter than most traditional diesel engines. Rather than an aggressive and predatorial roar, the boxer has a rather throaty purr. No, I don't bite... but I do nibble. Also, by throwing this engine in a vehicle with All Wheel Drive, many motorists can boldly go where few passengers car dare to go... off road.
And All Wheel Drive seems to be the plan. Subaru has announced that models using their revolutionary diesel design will include their famous Outback and Legacy (Liberty) models; and there are persistent rumors that the Impreza (now called the Impreza WRX), WRX (now the S-GT), and the Forester are in line to receive second dibs depending on how the Outback and Legacy perform.
Subaru is working on increasing the potential horse power of the boxer diesel engine, hoping to get as high as 161 hp, but also warns that this would naturally lower fuel efficiency while increasing potentially harmful fuel emissions. The possibility of a motor sport version has also been discussed, but Subaru's European testing General Manager, Hirofumi Senoo says that this would probably not be a good thing, as World Racing Class motors generally have more torque, but not much power.
In addition, some of the above mentioned models' predecessors are bringing something else to the table as well... an impeccable safety record. The Legacy, Impreza and Forester were all 2008 Top Safety Pick award winners according to a 2008 study by the Insurance Institute for Highway Safety.
Right now, it's only available in Europe, as Subaru is working to make the vehicles using this engine capable of meeting even the most stringent of U.S. standards and regulations. It looks to hit the U.S. markets in two or three years, consistent with earlier announcements by Subaru. Subaru estimates that it would cost around $1,500 extra to add the filter required to be in place under California's demanding laws.
Subaru says that mileage efficient diesel engines will benefit the average car owner more so than the split hybrid engines, as hybrids can only be used for in city travel, making them unreasonable for out-of-state or cross-country road trips. Even though Subaru and formal rival and current ally Toyota are now pushing hybrids more than ever, Subaru's sticking to its guns when it comes to providing quality diesel cars in the U.S., kicking diesel production to the top of their priority list. As Ikuo Mori stated, "There are many opinions. But currently, the voices calling for diesels are stronger than the voices for hybrids."
With the present gas crisis in full force, Subaru's looking to add a little market relief to the straining American economy. And even though diesel runs more expensively than gas, Subaru's economic boxer engine can make diesel the petrol of the future.