In fairness though Mize we have solid reasoning behind our lack of diesel cars, diesel cars do suck and all.
One of these days, you'll turn over the page of the calendar, and you won't need to be reminded that it's not 1991 anymore. Well, I suppose if you'd like to fantasize that you're still a teenager, then wanting to continue living in that time period might explain your need to delude yourself that you're still in the era when exotic sports cars could be had for under the price of an average home, and diesels still spewed clouds of noxious black smoke. You might as well continue to indulge in that delusion... but be careful where you tread. Espousing a personal delusion as a truth claim is the realm of
religion, not automotive engineering.
Diesel has lower emissions if you use the same rules as for gasoline cars.
Not in the U.S. The US doesn't measure emissions based on mileage the way other countries do. They really only measure air quality per unit volume of exhaust, not total quantity of exhaust gas components per unit of distance traveled. Yes, I suppose if the EPA actually understood that people drive distances rather than cubic meters of exhaust, they might put two and two together, but the domestic manufacturers are probably also happy to be able to keep certain competition out of the picture, and since gov't agencies are invariably ruled by the highest bidder, I think that pretty much defeats that idea.
Still, it does mean that, for instance, a giant honking SUV can theoretically have a better emissions rating than a small subcompact vehicle with a low compression ratio. Also, since emissions scores for each and every component is considered separately, the fact that a comparable diesel would have lower emissions overall is typically stamped out by the argument that its NOx emissions are higher... barring urea injection, that is). While urea injection does work, the EPA's argument against it is valid -- namely, that they believe the American public is too stupid to manage one more fluid to top off regularly.
The other major factor is that the quality of diesel throughout your country is very different (most of it being worse than McDonalds frying oil after three days in the pot), so you can't have a proper reference or ensure any consistancy as far as "guaranteed" exhaust limits go.
That part, I think is slowly being rectified in some states, but it is true that it's not yet implemented nationwide. Then again, there are some grades of regular petrol that aren't even available in all 50 states just because they don't want to encourage people to purchase cars that demand such fuels.
EDIT: as for that consumption figure, while it does sound impressive at first, it's not the real-life consumption. All of us lie there, the tests are rigidly defined and there's lots of cheating going on everywhere. Modern engine ECU will even recognize the test pattern and adjust accordingly.
Well, even without that, it would certainly explain why a 300 hp+ vehicle, petrol or diesel would score better than 30 mpg since much of what constitutes the testing schedule falls in the range of daily driving, where you're really not pushing into massive engine load. Diesel especially, would probably benefit here since it has the capacity to limit fuel flow rates to points far leaner than gasoline spark ignition. Closest that gasoline engines can do is cylinder deactivation under low load, which is quite feasible to produce good results in the highway driving schedule (also a good reason why the Mustang sees such a large gap between its city and highway rating).
That said, if it does something like that in general on highway driving, then for a daily driver, it's not impossible to say that 30 mpg is a realistic hwy result. Well, unless Ford actually says something about how they get there beyond "it's lighter and has more cams," it'll be hard to say for sure.
_xxx_ said:
New turbos are either two-stage turbo (a little fast rotor for lower engine rpm and a big one for high rpm), or adjustable blades, so that is not a problem any more. But still it's way less responsive than a gasoline engine.
Responsive on what scale?
You go to a drag strip and just about anybody will see the gasoline engine as the more responsive one that feels more powerful.
You do the same thing on a daily commute, and the average American driver -- the kind who isn't actively seeking to find and stay in the powerband all the time for the hell of it -- will almost invariably find the opposite is true because power will be available earlier even at low rpms. With a gasoline engine, you only get the same effect by having significantly more power everywhere at all rpms, and that's part of the reason why so many Americans think that a mid-size family sedan needs to have 400 bhp in order to be usable. It basically needs 400 because people want to wring out 100 out of that 400.