Popular Mechanics samples the Audi TT TDI
Last spring at the Geneva Motor Show, Audi introduced the first diesel powered version of its TT sports car, but so far has they have given no indication that they will ever bring it to the US market. Over in Europe the TT TDI is rated at a combined 44.3 mpg (US). The TT is using the same 168 hp 2.0L TDI four cylinder VW is using in the Jetta TDI cup race cars (the US spec Jetta TDI road cars use a 140 hp variant of the same engine). The folks at Popular Mechanics got to go over to the UK and take a TT TDI for a spin and came home impressed by the performance and fuel efficiency. In the course of some aggressive back road and inner city driving, they managed 39.1 mpg (US). The diesel engine easily revs to its 5,000 rpm redline and as with other diesels it exhibits strong acceleration at speed. The TDI rides a little harder than the gas powered version to compensate for the heavier engine. Now if Audi would just bring this one to the US we'd be all set.
[Source: Popular Mechanics]
Reader Comments (Page 1 of 1)
1985 Gripen 3:23PM (8/04/2008)
I am ALL FOR diesel as a stop-gap measure fuel choice on our migration course away from fossil-fuel-based ICEs. However, that said I will NOT sway in my support of the U.S. EPA for not allowing any diesel automobile into the U.S. that doesn't comply with Tier 2 Bin 5 emissions standards, especially in regard to NOx output.
If they have some sort of NOx catalyst and/or urea injection like BlueTEC to mitigate the NOx I would be very interested in buying a diesel automobile, as long as the diesel "premium" isn't more than can be made-up for in fuel savings over a period of say, 5 years.
Whenever someone posts here at ABG complaining about not having diesels here in the States they really need to realize it's because the European diesels are too dirty (in terms of smog and acid-rain-forming NOx) to be allowed here. I won't put up with more air pollution simply for the payback of increased fuel economy.
Also, not many people would buy a diesel vehicle if the price premium is much higher than can be paid-off in fuel savings.
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Richard 9:47AM (8/05/2008)
No, the reason we have not seen more diesels is the political instability of the U.S. The economics simply do not work for the auto manufacturers (U.S. or not) if there are to be differing emission standards for various and sundry states. (At least 16 are seeking that authority at this time.) The net result of this instability will be increased fuel consumption and dirtier air because of new technologies that will not be deployed. Oh, it will also increase U.S. dependence on foreign oil sources, specifically middle eastern sources. You can thank Speaker Pelosi for her efforts to further this disaster...see HR 5560.
why not the LS2LS7? 8:09PM (8/04/2008)
Actually, strong acceleration at any speed is not a characteristic of Diesels, as they are short on HP. I guess you mean without having to shift?
Article is interesting, it starts off by mentioning that Audi has decided to build a Diesel version of the R8, which they have not. They seem to have started down the path and then publicly canceled it.
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nagmashot 11:13AM (8/05/2008)
the R8 V10 TDI is not dead, if it gets into production is told by the managing board of Audi at the end of this year, the R8 V10 TDI only gets into production if the 1000Nm dual clutch midengine tranny gets production light from Audi managing board. This 1000Nm dual clutch tranny is currently in proccess to get it down to a payable production price
JSacharuk 4:04PM (8/05/2008)
I've got my own diesel Jetta, but that still means my experience is limited to one car. In any case, the off-the-line acceleration in the car is pretty mediocre until it gets running and you get up to a level where the turbo is providing boost. After that, it picks up and goes pretty nicely. I've heard this is pretty much the case for all decent diesel engines; the 0-60 time for the 123d is pretty middling, but accelerating from 60-100 is supposedly better than most petrol cars, even with only 200 hp.
Don't ask me to verify these statements mathematically or anything. I freely admit it's heresay that I'm passing on. :)
wxman 8:20PM (8/04/2008)
1985 Gripen -
You make several good points. The difference in fuel cost (unjustified based on everything I've seen) will likely impede LD diesel sales in the U.S.
Regarding emissions, ground-level ozone (the primary constituent of "smog") formation requires both NOx and hydrocarbons (NMHC). CO also can contribute since it behaves like NMHC in the atmosphere - only generally less reactive.
Ambient conditions encountered in virtually all urban/suburban areas in the U.S. ("VOC-limited") favor DESTRUCTION of ozone (smog) by NOx emissions, so control of NMHC/CO emissions is much more effective.
Diesel vehicles tend to be inherently low in NMHC and CO emissions, plus have very low evaporative emissions (a major disadvantage of gasoline vehicles), so a significant penetration of the T2B5 diesel vehicles could potentially improve air quality in many locations.
Furthermore, it is unlikely that a auto manufacturer will introduce any LD diesel vehicles in the U.S. that are not at least T2B5. Based on 2009 CARB certification data, the clean diesel vehicles may hit Bin 4 and even Bin 3 (they're certified "ULEV II" in California).
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why not the LS2LS7? 9:35PM (8/04/2008)
ULEV II is tier 2 bin 5, not bin 3 or 4. These vehicles are just getting in "under the wire", not matching what has been done with gas vehicles with SULEV II and such.
It's unlikely Diesels will drop below bin 5 at least until they try to start meeting Euro 6 in 2-3 years.
wxman 10:58PM (8/04/2008)
LEV II = Tier 2 Bin 5.
ULEV II is a category below LEV II and does not directly equate to a specific Bin.
The 2009 Jetta not only meets ULEV II, it meets Bin 4 in all regulated categories. It hasn't been officially certified by EPA yet, but it APPEARS it will meet Bin 4 based on CARB's certification.
Mike Hippenhammer 3:19AM (8/05/2008)
All you who nit pick on diesels emissions have got to look at the big picture. We are hoping that the diesels we choose will be high mpg type not the SUV type. Why don't you whine and cry about the current Trucks, SUV's, and RV's that are polluting 20 times more than an efficient VW or other diesels that are coming. You people have lost your minds chasing after the wrong polluters. Let's see an SUV that gets 15 mpg and is exempt from emissions requirements compared to a VW sportwagen TDI that can get 40- 50 mpg which compared to the the same gas model has the same or often better emissions standard. Get a life and pick on something that deserves to be castrated. I'll gladly buy a TT TDI !!!
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