BMW Balances Horsepower and MPG

As the auto industry scrambles to produce vehicles with greater efficiency, each firm is developing its own strategy and its own way to market its tactics. BMW uses “Efficient Dynamics” to describe its approach, which has a nice ring but has lacked much substance.
But a sneak peek of BMW’s upcoming 2009 7-Series sedan in Mirimas, France, gave a small group of journalists a chance to learn what efficient dynamics really means.

The core concept is to combine world-class drivability—BMW’s trademark—with exemplary emissions management and fuel-saving technologies. There are seven primary areas tactics:

  • Drivetrains optimized for clean combustion
  • Lighter weight construction, such as aluminum doors and side panels
  • Regenerative braking to supply and store energy
  • Electric power steering for greater efficiency compared to hydraulic systems
  • Air vent controls to enhance aerodynamics and reduces air resistance
  • Gear shift indicators informing the driver when to upshift or downshift for maximum efficiency
  • Low-resistance tires

One item not on the list is cutting back on power. The next generation BMW 7-Series will arrive in the United States next spring with a new, more powerful 4.4-liter V8 engine outputting 400 horsepower—40 more horses than the current model. Many would argue that increasing performance—especially to 400 horsepower—runs counter to efficiency goals. But BMW is trying to do at least two things at once: boost power efficiency and give drivers an exciting ride, hence the code name of “efficiency dynamics.”

In the case of the new BMW 7-Series, the resulting fuel economy is approximately 21 miles per gallon in the EU test cycle. Compare that to the current 7-Series’ combined 18 miles per gallon with a significantly less powerful engine. “The idea is that efficiency and dynamics are not mutually exclusive components. Advancing one should not adversely affect the other,” said Dr. Klaus Draeger, BMW project leader and board member, in an interview with Hybridcars.com.

BMW is not claiming that the 7-Series is the poster child for green motoring, but, at the very least, it indicates BMW’s direction for future products. With its approach, smaller models like the 3-Series, which currently gets around 22 miles per gallon, the level of efficiency could jump to the subcompact neighborhood, somewhere above 30 miles to the gallon. BMW’s start-stop system has already been added to the 1-series and some 3-Series models overseas and could be available in the U.S. by next year. There has also been speculation about a 7-Series hybrid in the next two years—but BMW is staying quiet about a full hybrid gas-electric system.


  • Boring

    Boring BMW
    Wow I’m so excited to see a V8 22mpg car that costs oh 40,000+ Sorry did i just fall asleep?

  • Mercedes-Benz

    Seriously…do we care?

  • VaPrius

    Is then EU test cycle down hill?

  • Need2Change

    Most who post here are happy driving efficient, low-cost econoboxs. That’s fine.

    I find it interesting what BMW is doing to increase it’s mileage wwithout adversely impacting performance.

    By the way, the 3-series can easily cost $40K. The V8 7-series is twice the price of a 3-series.

  • steved28

    I used to drive a 400hp car. It’s not as exciting as it sounds. There is no place to drive a car like that to half it’s potential. It’s more frustrating than exciting. IMO it’s actually more fun sometimes to drive a 4cyl 5spd and really work it.

  • Anonymous

    Adding horsepower to a V8 Waste Waste. How about V-6 or 4cyl turbocharged engine? I like the technology advancements in the BMW Class I just wonder why any car needs a V8? I won’t see BMW 7-Series NASCARS or towing construction equipment? Oh I know why you need a BMW V8, sometimes its hard to make it to your golf game so having the extra power to cut everyone off is worth it. Ha ha just shows that people can be arrogant even without Hummers all over the roadways today. Higher end car makers should show a little more responsibility and advancement eg. Plugin Hybrid, EV cars or at least downsized motors with turbo and other fuel savings add-ons.

  • JamesT

    Do you really think that someone who can afford a 7-series 80K car really cars about fuel savings? No they don’t but maybe in a few years Tesla, Volt, and other EV/Hybrid cars will change American’s obsession with V8′s as the only way to get extra power.

  • German Driver

    In case you haven’t done it, driving in Germany is not at all similar to driving in the U.S. One of the main difference is that many parts of the German highway system has no speed limit and cops are few in between on non-highways. You can be going +100mph and still get pass like you aren’t moving.

    BTW, I’ve been getting over 30mpg on the 3 and 5 series for the last two years now. And those cars are rated at 20mpg. Its all about learning to drive manual.

    This is more for the European-German driving vs. U.S. driving IMO.

  • Boom Boom

    There is always going to be a trade off between power and MPG. If you can get more power out of an engine, you can keep the power of the same engine level and get better mpg. If BMW can squeeze both high mpg and more hp out of an engine, imagine what they could do by maintaining the same HP and putting all the effort into MPG. At the very least they could offer a higher MPG engine with the same performance as the old model for sale and let the consumers make a choice.

    This is not just BMW who feels the need to increase HP every time they release a new model. Everybody does it. My hope is that at some point automakers will give consumers the choice of buying the more efficient engine or the more powerful engine. (The last sales numbers for the Toyota Camry had the 4cyl selling more than the v6).

    As for the german drivers, at some point, you’re going to have to come to terms with the amazing about of energy wasted (be that gas in a ICE or electricity in a electric car) by driving 100 mph. Compared to driving 55 mph, you’re basically throwing energy away. Sure time is money, but pollution has a cost as well.

  • Franz Leepkin

    Once again luxury firms don’t get it.

    For the prices these cars run they should all get 30MPG city and go zero to 60 in 6 sec.

    Until then I am not impressed with these feeble increases in MPG.

  • perfectapproach

    I’m just glad that BMW is entering the hybrid market…finally. If you look what happened in the 90′s, once SUV’s became popular, BMW, Mercedes Benz, Porsche, etc, all finally jumped on the bandwagon, albeit late in the game.

    The fact that these manufacturers are getting involved at all is a good thing, no matter how beneficial or effective the end-product is. Eventually, they’ll figure out that, just as the Accord Hybrid really didn’t work out, the whole “hybrid-car-for-performance-instead-of-fuel-efficiency” market won’t be the big money-maker they hope for.

    Unrelated topic: The Germany manufacturer’s are hip to using diesel-hybrids too…I like that idea. Why arguing about which is better when combining them would be even better then either one independently! :D

  • perfectapproach

    @ Boom Boom: “There is always going to be a trade off between power and MPG….”

    Wrong. 2 words: Fuel Injection.

    As technology advances, there will be those precious few technologies that actually increase horsepower AND efficiency. Fuel injection did it, and I think a powerful enough electric motor added to the drivetrain can do it too.

  • Need2Change

    Yes. Everyone has different needs, opinions, and wants. My sister’s husband drives 40 miles to work, and doesn’t understand why anyone would buy anything other than a Chevrolet Aveo which he bought new for about $11K.

    Some eat in McDonalds, others at Rudy Tuesday, and others go to $50/meal resturants.

    I find that most compact cars have too small seats for my 6’1″ frame.

    I considered a Prius and Honda Civic Hybrid in 2004, and the 10.5 second 0-60 was OK when I was in the car by myself, but acceleration was unacceptable when I had two other adults in the car. Also, arm rests and other things felt cheap — like the radio.

    Last year, I drove a Yaris, Matrix, and Corolla — Yikes. Let me out! I also drove a Prius, Nissan Altima, Nissan Versa, and Honda Fit. The Prius and Altima are too expensive. The Versa and Fit are almost OK.

    So I keep my Nissan Maxima GLE and Chrysler 300M Special , and keep looking for replacements — but can’t find one. And with 25 mpg, my monthly costs are far less than car payments on a Prius, Versa, or Fit.

    But I know that I need to change. Just don’t know what to change to.

  • polymer solutions

    This announcement is a yawner except to BMWophiles and car magazine editors who get a free ride to drive high performance cars without having to pay for them or worry much about their fuel efficiency. The concept BMW are touting is something General Motors have excelled at for years, fuel efficiency from larger displacement motors through excellent engine management systems. BMW is taking it a step further through lightweighting because at their price point they can more easily pass along the increased manufacturing and development costs to their customers. Jaguar has had the most fuel efficient luxury cars for years with their all aluminium XJ8 and BMW might now be trying to catch up. BMW makes great machines, but I think are overrated and overpriced for driving anywhere else but on the Autobahn. In fact, as a reformed gearhead, I now think high performance cars are obsolete dinosaurs and we just do not know it yet. Perhaps they will be “saved” by electric motor technology and ultra lightweight like the Tesla roadster, but perhaps gas powered high performance will be reserved for the exclusive domain of Sheiks and their relatives or the few ultrarich consumers who have no where to drive them legally – a sad thing to comtemplate but I personally have moved on.

  • Anonymous

    A comment to the person who can’t fit in compact cars. I’m 6’2 240lb and I drive a Dodge Ram and a 4 door Chevy Aveo (now mostly the Aveo) and I must say that its not that hard to fit into compact cars. I do admit that I enjoy the “boat” type of cars but the Aveo is a good car. Ok stop laughing. Its not a bad car if you are willing to put the seat back all the way. I think that all Americans should demand more value in their cars. I would say that sub compact cars have one of the best value rating of cars. Why large profits are made on huge SUV’s and higher end cars. Im not sure I fit into the Eco Box driver group but I would say that it seems to me that only Gear heads and people who buy cars for status would like this 80k car.

  • Boom Boom

    Tim,
    You miss the point with your 2 words. You’re saying that a 200 HP, fuel injected engine will get the same MPG as a 150 HP, fuel injected engine (if all other engine components are equal)? The trade off is not in the addition of the techonology, it is in the comparison of two vehicles with the same technology but with different HP.

    If you come up with a technology that increases both power and MPG, then why can’t you take the same technology, attach it to an engine that is smaller or less powerful and take advantage of the additional increase MPG. Hybrid cars are able to increase power with out using additional fuel compared to an equivalent non-hybrid engine, but if that increase in power is used to allow a smaller/more efficient engine in the car, you’ll get even better mpg than if you added an electric motor and kept the engine the same size. The only way you can get around this is if somehow you make an drive system that doesn’t increase MPG as you decrease power, and that seems impossible.

    Technology will make our cars more efficient, but it will not defy the laws of physics. Every year cars get more powerful. If instead, automakers held the power steady and every year bumped the fuel efficiency up, we’d be getting somewhere.

  • Crut100

    Nothing is exciting about it and their last sales results show that. Mighty BMW needs to wake up to the new US requirements of higher MPG. I currently own a BMW – an M5 (purchased when gas was much cheaper) but I will not buy another BMW until they get the fuel economy up on their cars to over 30mpg. Frankly, I’m hoping the Fisker Karma turns out to be a “real” car and not just vaporware and I’ll get one of those!

  • perfectapproach

    @ Boom Boom: I think there might have been a misunderstanding.

    What I’m saying is that, for example, a 200hp fuel-injected engine can get better fuel efficiency than a 150hp CARBURETED engine (assuming all other components, displacement, etc were the same). In this example, the fuel-injection provided both a 50hp boost AND a fuel-efficiency boost. Obviously, you can tune the carbureted engine to GET that 50hp boost, but at a drastic sacrifice to fuel-efficiency.

    I’m gonna try to find an example engine that really worked like that. I think the 2.8L V6 that GM made for some of the early-80′s Camaro’s were like that, but I wanna make sure I’m not talking out my @$$. Look for another post from me today.

  • Neil

    BMW has an amazing 123d in Europe. It uses start/stop technology, regenerative breaking, and of course, diesel fuel. It gets over 45 miles per gallon (US, not Imperial gallons).

    It is unlikely it would ever be brought to the US because BMW does not want to compromise its upscale appearance here by offering 4 cylinder engines. They made that mistake years ago by offering the chopped-off 118ti hatch with an underpowered 4 cylinder engine. The 123d has a twin turbo 2 liter 4 cylinder engine, so it is hardly underpowered.

    The best thing BMW has in the US now is a 128i with a paltry 19/28 MPG city/hwy. Later this year we may see a 335d sedan with an expected 23/33 MPG, which isn’t that impressive considering diesel has 15% more energy than gasoline. It really wouldn’t be worth it except the 335d is supposed to have 282 hp and 428 lb ft of torque. That is a lot of power!

    I am holding out for a much better mpg BMW, an Electric Zenn with ultracapacitor batteries or the Honda CRZ hybrid. It will definitely be a few years….

  • perfectapproach

    Ok, I did my research.

    I owned both of the following cars:
    1983 Camaro, 2.8L V6, carbureted
    1985 Camaro, 2.8L V6, fuel-injected

    Obviously, there will be 2 year’s difference in the engine design, but that’s not terribly much. The research I did was a combination of measurements I took when I owned the cars, and horsepower ratings when the cars were new. All of this information is verifiable from other sources.

    The naturall-aspirated (carbureted) V6:
    110 hp, approx 20 MPG in the city.

    The fuel-injected V6:
    135 hp, approx 22 MPG in the city.

    Almost exactly the same engine, the only difference being fuel-injection.

    I guess my point is that it is a RARE occasion indeed when a technology comes around that increases BOTH horsepower and fuel-efficiency. Fuel injection was one of those awesome technologies. Hybrid gas/diesel-electric engines is another.

    Maybe the German auto-manufacturers haven’t quite got the right idea by increasing the horsepower of their cars, and only improving efficiency by a couple of MPG. But that’s better than nothing.

  • Neil

    For the record, BMW has never made an SUV. Their X series of vehicles, which look like SUVs, are actually based on car platforms, not truck platforms.

    So saying that BMW missed the bandwagon on SUVs is really not true. In fact, they seemed to be the first to offer what is now termed a cross-over. Everyone thinks cross-overs are so innovative, but BMW was building them from the start.

  • Boom Boom

    As I said before, a hybrid drive train can increase both power and mpg at the same time (as did fuel injection, etc.). However, the fact remains that a 150 hp fuel injected engine is going to use less gas than a 200hp fuel injected engine (all other factors being equal). The same is true for a hybrid system. If you make a hybrid system that puts out 200 hp and gets 40 mpg, you’re always going to get better mileage from the same system if it can only put out 150 hp. That is the bottom line. There is always trade off between HP and MPG within the same engine/drive system. The point isn’t that you can never improve MPG and HP at the same time. This has been done by many different engine technologies. The point is that regardless of the system you will always sacrifice MPG by increasing HP and vice versa. In your example, the 135 hp V6 would probably get 24 mpg in the city if it only put out 110 hp. If you bumped your 135 hp V6 to 160 hp, you’d probably get 20 MPG, like the old carb engine. The same will be true with electric cars. More power will equal more electricity which will mean more consumption/cost.

    I’m not trying to tell people how or what to drive. I’d just like the choice to have a higher MPG car with every model update rather than more power. Sell cars with a big engine and a high-MPG engine. See which sells more. Then the market will decide which is more important. (Some cars do this, and recently more folks are buying the smaller engine.)

  • Gael

    Not True: direct-injected petrol engines are really close to having the same consumption regardless of the power. Just look at the new 2009 VW Golf which has just been announced with the 1.4 liter TSI engine: at 122hp, 6.2 l/100 km, and at 160 hp, only 6.3 l/100 km. With the DSG gearbox, only 6.0 liters / 100 km!
    Of course that’s true if you don’t go full throttle all the time, and I don’t think it is possible on any civilized road…
    Just for information, this is already true for electric motors. In fact, the bigger the electric motor, the better the efficiency. It means that a car with a 150hp e-motor and a car with one 1000hp e-motor will have roughly the same standardized mileage!
    That said, I just wish big car makers would stop wasting money making large-displacement V8s, and instead give us plug-in hybrids or full electric cars, which are the only way to go.

  • Boom Boom

    Come on, people! Stop proving yourselves wrong in your own post. An increase in hp (122 to 160) leads to a decrease in MPG (6.2 vs. 6.3). Your own numbers show it. The fact that the decrease is small, does not make it not true. As for the electric motors, I would imagine that it would take more energy to move a car with a 1000 hp motor one mile that a car with a 150 hp motor, just based on the weight on the vehicle. I haven’t seen any numbers on efficiency of electric cars to support the idea that in the future, when cars are electric.. if we get there, that big hot rods will use less energy than small econoboxes. If there is data out there to show that, I’d be interested in seeing it. (Since I fully understand that a electric motor has very different performance characteristics than an ICE).

  • NAvet

    Incremental mileage and performance increases are important for every manufacturer. BMW, and others work very hard to increase
    efficiencies on every aspect. It is truly the customer’s final choice.

  • Crut100

    Sold me BMW. Won’t buy another until they quit dinking around with tiny improvements and step up with some serious improvements in gas mileage. Come on the new Silverado full pick up is supposed to get 21MPG +.

  • Crut100

    A lot of them do – think about all those democrats in the House & Senate. Do you honestly think they are poor. Also, in a protest of one. I sold my 2006 BMW M5 due to the poor gas mileage. I’ve got my money sitting in the bank waiting for the first true luxury sports car that can get more than 35-40mpg and then I’m going to buy it. I also sent an email to BMW stating my wishes. I have owned big Bimmers for nearly 15 straight years so maybe the will listen. I encourage everyone else who has a BMW to do the same.