The world’s first horizontally-opposed turbo diesel engine

The world’s first horizontally...
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February 8, 2007 In 1896, when Karl Benz patented the first internal combustion engine, it had horizontally opposed pistons, and the flat boxermotor (the German term for flat engine) has been powering some of the world’s best known automobiles (Porsche, Volkswagen’s Beetle and Kombi f’rinstance), motorcycles (Honda’s Goldwing and BMW’s mainstay Boxer range) and aircraft (Lycoming and Continental) ever since. Japanese automotive company Subaru has used the boxer design almost exclusively and is now pioneering a new phase for horizontally opposed piston engines with the release of the world’s first horizontally-opposed turbo diesel engine. The Japanese all-wheel drive specialist will be displaying an entire drivetrain at the 77th Geneva International Motor Show next month.

Subaru believes passionately in its boxer engines which are more compact than in-line units and provide a much lower centre-of-gravity.

This reduces body roll for safer cornering and also enhances handling precision such as during a sudden lane-change manoeuvre on a motorway.

Due for its first vehicle application early next year, the Subaru ‘boxer’ turbo diesel is a highly rigid unit with low levels of noise and vibration.

Not only does this eliminate the need for a balancer shaft which counters uneven combustion pressures and general roughness, but Subaru’s first diesel is as compact as its petrol sisters and combines unusually strong pulling power at low engine speeds with high-rev throttle-response.

William H Lanteigne
4 year old article, and the boxer turbodiesel still isn\'t available in the US. I\'d love to see this in a mid-size half-ton pickup.
Whilst this may be unique in having a tubocharger, Commer were using horizontally opposed supercharged engines in their commercial vehicles in the 1950\'s. The design was unusual in that each cylinder had two pistons, and their motion was transmitted to an underslung crankshaft by rockers. Even more unusual in its day wa the fact that it was two-stroke.
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Detroit Diesel Allison Division of General Motors made a flat, opposed cylinder, air cooled Diesel engine with twelve cylinders and two turbos on it, one for each side. They were used by FMC in some of their Army tanks back in the 1960s and 70s. CID was 1250 as I recall being told when I was a tank mechanic for them. The M48 would get about 3 miles per gallon of fuel. That engine supposedly began life as a gasoline engine that was a real pig, needing 3 gallons of gas to go one mile!
I believe Fairbanks Morris had a vertically opposed piston diesel which was used in subs during ww2, was supposed to be very silent..
they need to go back to 1980 Mercedes diesels they built,inline,no need for balance shafts,cast iron,able to run easily over a million miles.Now a days engines are built from junk materials.
Better yet how about train engines that had real opposed piston engines. The pistons traveled towards each other with no cylinder head in between. There were two crank shafts with a common bore. I believe they were made in both two and four stoke configurations and probably used super charging or turbo charging as well. The challenge lay in keeping the two crankshafts connected and in a precise configuration.
Whilst touring Europe in 1973 I picked up a 2nd hand DAF car which was 2 cylinder petrol and horizontally opposed... It also had what I think is called a variomatic drive.... The rear wheels were belt driven. The gear lever was a forward or reverse, which meant you could drive as fast backwards as you could forwards.. AS you drove off there was no sound of gear changing just an increasing whine which only occupied your thoughts because you were listening for gear changes.. UTube has a great clip of the Variomatic working.
The Leyland 12 cylinder multi-fuel, horizontally opposed compression igniton engine of a Chieftain tank, introduced into service in the 1960's comfortably beats the Subaru! But I am reluctant to claim it was the first; inevitably the Subaru will be considerably more reliable.