Autoblog

Americans don't have the whole story on Diesels.

As long as Diesel engines are so much larger and heavier than gas engines, and engines are located in the front of cars, it's gonna be tough to make a true performance car from one. Unless by performance you mean a straight-line dragster.

Yeah, yeah, BMW Diesels whatever. They do really set the standard for Diesel performance (at a significant cost), but again, they mostly are measured by how well they accelerate and how quiet they are.

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I think the reason Top Gear avoids diesels is because you can't rev super high with them like you can some performance oriented gas motors. This brings HP ratings down, and so makes the car look less "MOAH POWER"-worthy on paper. (I love my TDI more than any other car I've had, BTW)

Porsche doesn't "shun" diesels at all costs, either. Just recently, Autoblog had a story about Porsche considering a diesel for the Cayenne (I can't remember if it was Porsche that was considering, or some outside entity).

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It depends on what you want out of a car. The E320 Diesel, for example, is respectably slower to 60mph than the E350 is.

Diesels are inherently slow to rev, low RPM engines that tend to produce very little horsepower for their displacement (which is to be expected, as horsepower is a function of torque and RPMs)-although as diesel injection technology has matured, a lot of these inherent characteristics have become less apparent.

So, all that being said, they're not necessarily deally suited to sports cars, particularly if you expect something like an S2000 that'll rev to the better part of 9000rpms.

However, the low revs/high torque nature of diesels also makes them more similar (in some respects) to the big American V8s of the 60s and early 70s. A lot of the 428s, 440s, 454s, 455s, 460s, etc. were redlined at or below 5k, but they often produced well in excess of 400ft-lbs of torque, too.

I can't really answer your question one way or the other; all I can tell you is that I enjoy driving the more powerful diesel Mercedes (e.g. the 300D 2.5 Turbo), and I'd be very interested in a diesel WRX with say, 250hp and 400ft-lbs of torque, to use as a daily driver so I can park the STI. In fact, I wish BMW would bring the 335d over here and add AWD. I'd buy a 335xd coupe tomorrow if they'd make one and sell it here.

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Actually, diesels just deliver peak power in a very narrow RPM range. That means you have to be a good driver and change gears frequently to keep rated power on tap. Jeremy Clarkson is not a bad driver, but he's not a brilliant one, either. Check out his piece on going around the Nurburgring in a diesel-powered Jag to see how frustrated he gets with the effort of keeping up power levels on a very challenging circuit he hardly knows.

Modern gasoline performance cars deliver something close to rated power over a much wider RPM band, so they're easier and more fun to thrash and power slide etc. at the limit.

Of course, the problem would go away if the position of the accelerator pedal were interpreted as power rather than torque demand as is the case today. The drive train controller would then figure out which gear to select to deliver the required power most efficiently based on current vehicle speed and the engine's SFC map. The match would be perfect with a CVT, though an AT with a large enough number of discrete gears (6 or more) would also do the trick.

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wow, thanks for all the insightful answers. I guess it's wrong to classify all diesels as similarly utilitarian. That 335d sounds amazing, 282hp and 428lb-ft is crazy. I'd have to drive both before deciding, but I would definitely have a hard time choosing between the 335i and 335d. I guess diesels are very different, and it's up to individuals to see what's better for them.

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hey Whynot:

I will not say Americans want diesels, I would say many Americans.
I for a fact don't want a diesel, nor like them.

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rgseidl:
Actually, no. Diesels not only make power in a much smaller range, but they make a lot less power for engine size. That means worse peak performance, not just that you have to shift at different times.

Still, at low pedal pressures, Diesels are more efficient than (non-lean burn) gas cars, which is why they are great on the highway.

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The present trio of Clarkson, May and Hammond present the image of shunning diesels but Clarkson has himself raved about a number of larger-engined diesel models.

Top Gear used to be a more sensible television car programme, where diesels, along with many more ordinary cars, were tested and appreciated.

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Agreed

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That is the same point I was going to make. I was in Santa FE, NM this weekend where I saw $3.97 for diesel. It was approximately $0.60 more per gallon than low grade.

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Ditto here....diesel is $3.89 to $4.09, while regular unleaded is $3.19 to $3.39 in the Milwaukee area right now.That's more than 20% higher

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I filled my TDI the other day at $3.749/gallon. The gasoline at the pump next to it (regular unleaded) was $2.999/gal. I get about 38.5 mpg average, roughly 55% city, 45% highway. That's 9.7 cents/mile for me. A gasoline car needs to pull 31 mpg with similar driving to do better even with this $0.75/gal price differential. My boss gets 32 mpg in his Chevy Cobalt, but he does mostly highway driving.

You are correct that this largely annihilates my payback period. If this were to hold, it'd be 111,000 miles before I saved versus the gas version of my car. However, diesels tend to retain a resale value that would slash that period drastically.

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All I want is my stinkin' Diesel Hatchback Impreza with a manual transmission. Is that too much to ask?

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Sacrilage!

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I don't care, I'm going to buy a diesel car anyway.

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But driving a car/truck that gets 15mpg is AOK?

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