The 100 MPG X-Prize Loser

In 2009 and 2010 entries for the 100 MPG X-Prize will run their cars in road tests to determine the winner...
A car that might lose...if entered...would be the 2001 Audi A2 1.2 TDI.
The A2 1.2 TDI is a three-cylinder turbo diesel. The car has an aluminum frame and bodywork and weighs 1881 pounds. The car has four seats, four doors, and a hatchback. The diesel engine makes 60 horsepower and the car gets up to 95 MPG.
Problems ? Well the 0 to 60 mph acceleration is 14 seconds. And there's no air-conditioning or power steering. Oh...the tires are too small.
Other problems ? Well...the fuel mileage in rigorous testing would probably be something like 70 MPG CITY and 90 MPG HIGHWAY or say 78 MPG COMBINED.
Heralds ? Well this was a production vehicle ! And this is a four seat vehicle that gets up to 95 MPG...
http://www.audiworld.com/news/01/A2TDI/content.shtml
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The Audi A2 1.2 TDI was produced from the years 1999 to 2005 ...
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The broader point is that if a small four-seat car can weigh 1881 pounds and get 95 MPG...then a mid-size car can weigh 2500 pounds and get 50 MPG. Go with gas instead of diesel and that's 67 MPG for the small four-seat car and 35 MPG for the mid-size car.
Well the weight of the Audi A2 is key and the engineers say that it is an aluminum space frame. But they also mention that some of the bodywork is a stressed-skin that adds strength to the frame.
Well a space frame is any frame that is mostly triangulated and that does not have primary beams that overwhelm the rest of the frame size. Then a space frame with a stressed-skin is often called a monocoque. I guess a frame with large beams and minor triangulation would be a girder frame or a backbone frame. But I see one source that compares the established automobile uni-body frame to a monocoque frame. Well a uni-body frame is mostly folded sheet metal with little frame while a monocoque frame is an actual frame with a skin or bodywork that is functional as structural. Now the monocoque is lightweight because the strength added by the stressed skin is taken off the frame but with the frame maintained.
Anyway...the Audi A2 looks more like a girder frame with minor triangulation. (A space frame looks like a power transmission tower and a monocoque frame looks like a power transmission tower with a skin riveted to it.) But they must be serious because they could have used fiberglass bodywork over a girder frame or over a space frame. And the result does the talking here...
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PolicySpy wrote:

In earlier discussions, I mentioned the 1993 Ford Festiva. That was a steel unit body, with a little beam fabrication effort between the front and back seats. The 1.3 port injection was rated at 57HP It weighed lighter than the Audi, but balanced lively acceleration and top speed against a 43 MPG fuel consumption.
Brian W
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The subject car was the 2005 Audi A2 1.2 TDI diesel...
http://www.audiworld.com/news/01/A2TDI/content.shtml

For the 1993 Festiva I could only find the 3-door hatchback...versus the subject car as a 5-door hatchback.
So the Festiva 3-door hatchback has a wheelbase of 90.4", a length of 136.8", a width of 63.2", and a weight of 1598 pounds.
The Audi A2 5-door hatchback has a wheelbase of 94.69", a length of 150.63", a width of 65.87", and the weight of 1881 pounds.
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