Quote:
Originally Posted by sidebar78
didn't pass emmissions tests my eye! a vehical getting that kind of milage is burning most of it's fuel and running clean
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As someone who's tuned diesels to meet emissions I can assure you that better fuel economy does NOT necessarily mean lower emissions. With CO and hydrocarbons, that's generally the case. NOx generally goes the opposite way as efficiency because NOx is driven by temperature. Hi temp = Hi NOx = Hi efficiency. Just look at what happend with the lower NOx emissions that came in in 2003 for heavy duty trucks. Fleet efficiency had historically improved by about 0.5% every year. In 2003 it DECREASED for the first time because of the stricter NOx limits.
As far as the car goes it is a pretty cool story. I remember hearing another story about a group of engineers in the oil crisis modified a VW diesel and got 100 mpg (under some very ideal conditions). I'll have to see if I can find the story.
But folks shouldn't be too amazed at the car. It was an 1.8L turbodiesel in a fairly small passenger car. Just look at the small diesel cars that the Europeans are running these days. They're pretty much in the same range (Remember, 80 mpg on the highway is very different from a 80 mpg highway
rating). I think the VW diesel Rabbits in the 80's had highway ratings in the high 50's and I think those we naturally aspirated.
Now, making a car like that can meet current NOx limits (and PM limits w/ a DPF), and still make it affordable in the US market is the challenge...