Diesel, without the diesel: Mercedes-Benz debuts DiesOtto
Diesel technology has improved by leaps and bounds, but the trouble is, it still runs on diesel. In the American market, at least, finding a diesel pump is still a pain compared to filling up with conventional gasoline. Mercedes-Benz says it's found the solution with a new developmental powertrain concept it calls DiesOtto.
We first reported on the project a couple of years ago, but the German automaker now has a functioning prototype. Rather than actually running on diesel, the DiesOtto engine is said to incorporate the benefits of a diesel engine, but runs on regular old unleaded. The prototype is a 1.8-liter four-cylinder engine that uses direct injection, variable compression, turbocharging and something MB calls "controlled auto ignition" to deliver 238 horsepower and 295 lb-ft of torque, with a claimed return of "less than 6 liters per 100 kilometers", which translates to 39.2 mpg. Those numbers, Benz claims, are not based on a small car (like the C-Class or smaller) but on a large sedan (like the S-Class). They may not be entirely revolutionary figures, but any way you look at it, they're damn impressive.
Mercedes hasn't put a timeline on producing and marketing a powertrain based on the DiesOtto prototype, but says it's a "feasible proposition in the midterm". We certainly hope so.
Gallery: Mercedes-Benz DiesOtto
[Source: Edmunds' Inside Line]
Reader Comments (Page 1 of 3)
Ian 5:01PM (7/25/2007)
Hang on. This ISN'T adiesel engine it's really a highly developed gasoline engine! So why the diesel headline?
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The Other Bob 5:37PM (7/25/2007)
Diesel is named after the guy who invented the process involved in a diesel engine, which I believe the fuel is named after - not the other way around. The diesel process is where the fuel ignites by compression, not a spark. It doesn't matter what fuel is in it it still is running like a diesel.
Even have an old car run after it is shut off and you refer to it as "dieseling"?
Ian 8:50PM (7/25/2007)
Ahhh.
Actually it should be called the Stuart engine after Herbert Akroyd Stuart. Perhaps non diesel fuel consuming, compression ignition engines should be called "Stuarts" hence forth?
vdk 9:43PM (7/25/2007)
FYI in a diesel engine the fuel doesn't ignite by compression, it is actually sprayed in a very dense air mixture thus the ignition... it's friction not compression... oh yeah... and diesel doesn't compress it's a liquid.
Barney 10:21PM (7/25/2007)
Re:Vdk @ Jul 25th 2007 9:43PM
FYI in a diesel engine the fuel doesn't ignite by compression"
Yes and no. Air is under put under extreme pressure and gets hot doing so. The hot air ignites the oil.
Lee 11:33PM (7/25/2007)
actually vdk, it is the compression that causes it to ignite. But its the compression of the air not the diesel, the air reaches almost 1000c as its compressed, as the diesel is sprayed in it ignites. The heat increase via frictional effects would be almost negligible in comparison to those of compression.
James Sonne 9:43AM (7/26/2007)
The heat of compression is caused by friction of particles.
Lee 10:53AM (7/26/2007)
The increase in temperature due to compression is a consequence of the ideal gas law. As the volume decreases more collisions occur between particles in the air, hence the amount of kinetic energy transferred is increased. Therefore temp increases as the temperature of a gas depends on the average kinetic energy of the constituent particles.
Kowell 5:01PM (7/25/2007)
1 to go please!
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DriftPunch 5:03PM (7/25/2007)
Now that's technology I like to see in a car! Fuggetabout Nav, Onstar, auto-nut-scratching, etc...
Develop it well, and I'd actually be interested, something I never thought I'd say toward a MB.
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Mike I 5:48PM (7/25/2007)
Are you kidding me? I can't even remember the last time I've seen a gas station here in California that DOESN'T offer diesel.
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Mike 5:05PM (7/25/2007)
" but the trouble is, it still runs on diesel. In the American market, at least, finding a diesel pump is still a pain compared to filling up with conventional gasoline"
Depends on your perspective I guess, in my view a diesel fueled vehicle is an advantage not "trouble" and I don't recall seeing many diesel powered vehicles sitting on the shoulder out of fuel.
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Bill 5:28PM (7/25/2007)
This old complaint is sort of an old wives tale. I honestly don't think there is any diesel availability problem in America anymore. Is there anywhere where you don't find diesel trucks or busses on the road because they don't have access to diesel? Yes their tanks are larger, but c'mon. Just about every gas station has diesel, and if it doesn't the one across the road or down the road does.
Barney 5:30PM (7/25/2007)
Reread Mike. It runs on regular unleaded.
Bill 7:23PM (7/25/2007)
Yes I read, but I don't think that there is a factual basis of the claim that diesel is hard to find, and the quote in the article perpetuates a 30 year old myth.
zamafir 10:35PM (7/25/2007)
Having owned diesel cars since 2002 I can gladly and happily say I've never had issue filling up the car, ever, including 20 round trips from san diego ca to spokane wa (both the coastal and inland routes).
AMcA 10:25PM (9/06/2007)
It's not so much trouble, as it's a tiny extra increment of anxiety. One more thing to think about.
Ask a diesel driver: you fill up not when your tank is empty, but when your tank is down a ways and there's a diesel station nearby.
Not a problem. Just something you have to think about a bit.
afg350ci 5:12PM (7/25/2007)
Wasn't Bob Lutz just talking about gas engines that are as efficient as diesel?
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Derek 6:43PM (7/25/2007)
Yes, I believe Bob was talking about homogenous charge compression ignition (HCCI) engines, which sound very similar to the DiesOtto engine.
El Calor 5:18PM (7/25/2007)
WOW, sounds like the best of both worlds!
http://www.benzForum.com
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