Mercedes (AMG): "looking at direct-injection turbo engines as an alternative."

AMG with turbo sounds more tuner than high-perfomance exotic

reeeepost :)

I'll take an MB turbo any day.

This makes a lot of sense for MB. I always wondered why they still clung to superchargers.

no turbo lag, beefier engine feel

PlanoA4,

This makes a lot of sense for MB. I always wondered why they still clung to superchargers.
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I think because of two reasons:

1) Tradition: the great Mercedes' race cars of the 1920s and 1930s had Kompressors installed on them that could be manually switched on. The infamous 500K for example had a 5.0 inline-8 with 100-hp. Turn on the Kompressor and power went up to 180-hp. Other famous cars with superchargers from MB: SSK, SSKL and the 540K.

2) Torque and fuel economy reasons. The supercharger added more torque, which aids acceleration and fuel economy. And I think it was part of the MB tradition to use a supercharger with their performance cars (see reason 1).

;)

Firts BMW and now AMG. Everyone is following Audi's footsteps and using turbocharged direct injected engines.

Will,

So the choice is either superchargers or turbos? What ever happened to naturally-aspirated being the preferred choice? (...Lexus...ahem...)
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If you knew your BMW or Mercedes history, you'd see that they've created N/A engines with high horsepower per liter ratings. There were for instance some Mercedes racecars in the 1930s with a 3-liter engine and over 400-hp, naturally aspirated.

So Lexus is all of a sudden the new performance king because of their 3.5-l V6 with 306-hp? Give me a break. BMW and MB could make more powerful versions of their V6's if they wanted too, but they have to optimize the engine for various markets. The power output of the C350 or 330i / 335i is more than adequate for sporty driving and fun. Lexus made the IS350 for America. It's not even sold anywhere else except in the US.

There are various taxes across europe.
A 3.5 litre almost too big, but 3 liters is also kind of pushing it.
However BMW got it better because of:
- lower displacement
- better fuel efficiency
- lowere emissions

Thus Direct injection + 2 small turbos.

Let's make things clear, turbos + direct injection (+ supercharger maybe like VAG's TSI) are the future, for now.
That means, just like with diesels in Europe, you either have em, or you pack you bags.

Will, you seem to forget the obvious.

Increasing the BHP for a naturally-aspirated engine either involves bigger displacement, or a more peaky delivery to extract the power.

This means (ie. Honda and VTEC) that the engine must be driven at much higher rpm to extract all the power, as rpm and power are directly related.

The difference with Mercedes-Benz and their supercharged engines is that they have torque and power low down in the rev-range, whereas an equivalent power N/A engine would have to reach much higher rpm to achieve the same figures.

In the end, engineers don't just look for gaining BHP, they look for drivability. Big luxury sedans, are by nature relaxing and effortless. Mating these attributes with a peaky, high-rpm motor just won't do, regardless of the engine's sophistication. Especially as heavy luxury sedans require torque to move them, and high-revving engines aren't known for their torque....

The Bentley Arnage has a 6.75 litre, twin-turbo V8 motor. It's relatively unsophisticated, yet the way it delivers its power, (effortlessly and in big chunks of torque) matches the nature of the car perfectly.

Maybe you Americans are guilty of number-bashing to the point where you lose touch of reality, because pure BHP figures don't show the whole picture.

High-rpm motors certainly have their place (the new RS4 is a perfect example of how a different engine philosophy can change the whole nature of a car) but then so do forced-induction cars.

And I certainly don't want to hear people say turbo-charging is just a 'lazy' option for engineers to get more power. The amount of expertise and technology involved in matching a turbo to a motor in perfect harmony, eliminating lag etc. is something not all car manufactures have managed to do.

Let's bring out an old cliche: "Different strokes...."

turbo charging saves weight and improves fuel efficiency.
why? because wehn the turbo isn't at full tilt the engine behaves exactly like its real size, rather than its turbo size (ie saabs 2.0t behaves like a 2.8 or something with turbo).
supercharging saves weight, but doesn't increase fuel efficiency, as it is directly attached to the engine.

note about the arnage; when it was introduced with a bmw twin turbo 4.4 (oh wait bimmer have used turbos before) people complained about it, and its 5 speed gearbox. vw took it out, replaced it with the 6.75 turbo and a 4 speed and it flew off the shelves.
the 6.75 V8 has been around for 50 years, has doubled in power and got 99% cleaner.

Actually, a turbo set up is probably lighter than a comparable super charger set up, and more efficient.

efoxS4

The RS4 achieves 420hp from natural aspiration, and the M3's small inline six acheives an astounding 333hp. That's really a lot for a six cylinder, and puts even the IS350 to shame. If BMW made the 335s and 535s standard with the outgoing M3's engine, it would be a fine world, wouldn't it?
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You're forgeting certain things, like european taxation policies.

M cars/engines really don't have to worry about fuel consumpion and/or emissions.
The regular do.
The NA 3.2 I6 burns more fuel and its emissions are higher than of the 3.0 litre TT I6.
Witch means taxes, taxes, taxes.

Will,

I'm sure that any automaker can make a more powerful V6, so still the question remains, why don't they?
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Why should they? Let's take the MB C350 for example. 272-hp I believe. That's A LOT. Now, coupled to that 7-speed automatic, it should have impressive performance. This engine was designed with Europe and the US in mind (and other markets). The power output is adequate, more than adequate. In Europe, 272-hp is a lot. 3.5-l is considered BIG. The taxes on this thing are incredible over there. MB optimized the engine for both Europe and America in terms of performance, emissions, fuel consumption etc. Perhaps if the engine had 300-hp, fuel consumption would drastically increase but performance would still be the same. So if performance is still the same with a 300-hp version, but the 272-hp version gets better fuel economy and emission ratings, which engine are you going to choose to produce?

"Give me a break." The IS350, along with the C350 and the 330/335 were ALL vreated for the American market where larger engines are more favorable, so yes, in those terms, the IS350 is everything the American compact sports sedan buyer wants.
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See my post above regarding the C350. The 335i was designed to appeal to power-hungry BMW enthusiasts and driving purists. I agree with you that this car was first and foremost designed for the US. I expect European sales of the 335i to be very low.


By the way, you can also get the IS250, with a 204-hp V6, and there's an IS220d(iesel). What do you think would happen if the IS350 were offered to the Europeans?
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Yes, the IS250 and IS220d are the only IS the Europeans get. They need however an "IS180 or IS200" (4-cylinder) and more diesels.

The IS350 in Europe? Hard to say. Like I said, Europeans are taxed on engine capacity, power output, fuel and fuel consumption. When I travel to Europe, at least 5 times a year (business), I rarely see E350's or 530i's or 330i's. What you see over there are 320d, C220 CDI's, E220 CDI's, A4 2.0 TDI's...those kinds of cars. The IS350 will sell - but in small numbers. The German brands sell most of their 330i's or C350's in North America. So Lexus is doing one thing right by keeping the IS350 out of Europe. The real competition in Europe is between the small gasoline and diesels. The IS220d will go against the 320d, C220 CDI, A4 2.0 TDI etc.
Well, for starters, you guys would criticize them for not offering smaller engines!

you are right, bmw530i.
we like small diesels here, like the 520d,, a6 2.0tdi, 320d etc.
335i sales will be equivalent to last model 330ci sales, which i see quite a few of. but still the 325, 320, 318, 320d, 330d, 335d will sell more (we're not getting the 328).
note that the 320d is faster than the 320i.

diablo69:

Interesting article. Is this the technology Audi used with the Roadjet concept, which had a 3.2L engine producing 300 hp? A 3.2L TSI with 300+ hp would be a perfect bridge between the standard 3.2 and 4.2.