BMW says 3.0L twin-turbo diesel cars coming to U.S.

Sweet deal.

turbos? why can't they just make it naturally aspirated like Audi does?

Um, Diamond, which engines are not turbo? Unless I'm mistaken almost all diesels have turbos on them. And doesn't the TD in TDI stand for Turbo diesel?

Audi has a 500 h.p. V12 diesel in a Q7 concept going into production soon. It is normally aspirated. There is also an automotive supercharged diesel somewhere but I forget who makes it. I have never trusted turbos since the early ones crapped out with extreme financial consequences. Turbos operate constantly in a high-temperature environment which raises a red flag for me. The auto industry does not use expensive aerospace alloys for its turbos and Honda has gone so far as to locate some of its turbos further down the exhaust system where temperatures are cooler -- a good precaution perhaps but a less efficient solution.

Audi does not have normally charged diesel engines. Due to the fact that diesel is more efficient, it emits considerably less heat than a gasoline engine. This is why you do not need superalloys (aka "aerospace materials") to run.

The V12 diesel is a bi-turbo in a sense that they have a turbo for each bank of cylinders. The BMW system is different: they have a smaller diameter turbo wheel boosting at low rpm, and a higher diameter wheel for higher rpm levels. The engineering marvel is that you cannot feel the changeover between the two, the car just pulls with the unbelievable strength of a locomotive.

JWalkerLegrande, you are correct. I just looked at the Q7 V12 TDI engine drawing and it is clearly a turbo. The "T" in "TDI" should have tipped me off.

However, I still do not trust turbos even if they do run at "lower" temperatures. I would trust them only if I knew the exact alloys used fort the blades and housing so I could assess their reliability. I also need to know how exactly the turbo bearings are cooled for a specific vehicle.

Ever heard of the 1.8T? That "T" don't stand for Tickle.

When you're getting a bmw- what's another 2-3K?

I used to sell BMWs, I was surprised many times over about price being an issue on cars this expensive. Everyone has there limits.

At least for consumers like me, there comes a time when you say, "that's enough." You can always get something better for just 2K more...

Had the 335d been available when I got my E92, I would of gotten the diesel. Also would of chosen x-drive had I known it was coming on the coupe. Oh well. Next time.

Eh, 6 Series is too big and heavy. I'd rather have a 335d- which actually has a better back seat AND better performance.

$2-3 Thousands more on an already $50+ 335i is a stretch. BMW should bring the 123D over instead, and keep the increase on that to around $1,000 and they will be a lot more successful than the 335D with 2-3 thousand increase. For your information, the Mercedes E-class diesel (Bluetech) is only $1,000 more than it's gasoline (petrol) sibling.

yeah but there's a big difference between the E320d and the 535d. Big, big difference. I've driven the 535d, I'd pay it in a second.

Well, which one gets better mileage? I'm sure the 535d has incredible performance but the E320 Bluetec gets almost 40mpg in real-life highway driving-- and that's what buyers of diesels really care about. It still has good performance, though.

I'm not saying I'd get the Bluetec over it. I wouldn't. But it's just an observation.

Where is a 335 50k+?

A loaded 335 (petrol) E92 coupe is about $50K in the US.

I'm another E90 owner that would love 427 torques to play with. Plus the thing can be chipped to over 500 without much bother.

Best automotive news!

SWEET!

Are you sure the twin turbo diesel engines in the 335D can be chipped? I thought it wasn't possible to chip a diesel turbo engine.

Why not? You hold the wategates closed longer, you go faster!

I have a friend with a "chipped" GMC Duramax. I guess diesels can be chipped where fuel injectors and air intake are computer controlled.

For DiamondJim:
The vast majority of Audi's diesels <u>are</u> turbocharged. That's what the "T" in "TDI" stands for. Only a small handful of Audi's diesels (just a few small 4 cylinder engines) have been non-turbos.

X5 is a sure thing, 5 series makes sense, if they really want to make diesel the performance cutting edge, 3 series as well.

Be careful when comparing specs on the BMW3 vs. BMW 5. I have a 2008 5 series catalogue (printed in Germany) and it has a dimensional drawing of the 3 series instead of the 5 series. This is a serious error as, for a minute, I was led to believe that the 3 and 5 share an identical platform. The BMW website had the correct dimensions for the 5 however. I guess from now on I'll take my tape measure to the showroom when visiting a BMW dealer.

Another word of caution. BMW has two different 6-cylinder engines for the 5. One is the N52 and the other is the N54. The N54 is more robust as it has an aluminum block with csst iron cylinder liners. Unfortunately, you can't get a normally aspirated version of the N54 engine.

The N54 is the new twin-turbochared 3.0 litre based on the older M54 naturally aspirated 3.0 litre. The N52 is the newest naturally aspirated 3.0 litre which replaced the M54. The N52 was deemed not suitable for turbo-charging because of it's aluminium-magnesium engine block.

The N52 is well proven at this stage though and is a robust and reliable engine. Its also hugely advanced, its crankcase is made entirely of magnesium and aluminum, a first in the world of engine construction. It is also one of the lightest engines of its size class in the world.

My point exactly Kinger, the N52 block is lighter but not as robust as the older N54 block.

I love it when you can never admit to supporting or liking a great new German product. You're feigning envy. Although, you don't have to be envious- just buy one, they're available to everyone. You won't be disappointed.

Because they're super good.

"I forgot to mention that I love how whenever a Japanese car matches the Germans in performance, then takes it home with mileage and emissions, rich ppl don't care about mileage."

You're wrong. I'm guessing you're talking about the GS450h. Let's review:

• As fast as a 535i

• Similar mileage to 535i

• More expensive than 535i

• Much smaller trunk than 535i (yes, rich people DO care about trunk space!)

• Not as satisfying to drive as 535i

• Won't get nearly as good mileage or performance as 535d

So, tell me, why would I get a GS450h over it now?

Why does it have to be "not bad?" Can't you just admit that the BMW makes more sense? It's just as fast/faster AND gets better mileage! What is it about this that isn't getting through to you???

It will do better than 33 on the highway- I'm guessing 36. That's over 10 better than the Lexus. And, FYI, according to Lexus the GS450h averages 26.5MPG US. Not so impressive. You were clever not to check the Lexus US website- nice try.

Deception? When they're officially released here they will have accurate fuel economy ratings. Obviously whoever compiled the article took the European readings.
Why do you have to be so biased against anything European or non-hybrid? These cars will put out less CO2 than any Lexus hybrid.