I would say the mb diesels do not necessarily lend themselves to super high mileage here in the states...we don't have a 4cyl from them. If I were to buy or build a car based strictly on economy id get the vw tdi...also the new skyactiv mazda diesels coming soon have a lot of hype.

As far as "hypermiling" I've noticed that few members on here do so, and then when mpg figures come back they are shot down...been there and done that. Some modifications that I've seen include replacing the rear end for lower gearing for highway cruising though, and some tweaking of the fuel delivery (I.e.) alda

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth