Obviously flatting out the Prius gives better mileage. But you don’t go pedal to the metal with your car every mile, do you?

I think I am one of those who got the weight wrong. When I read the figure it was for the BMW 135I and it was around 3680lbs.

I never doubted that the new M3 engine was lighter. It wasn’t an issue to me.

But I will take exception to an M3 getting better f/econ than a Prius, unless you are talking about these cars basically racing around the track rather than cruising. You might want to site the specific issue or episode. Though you have to take anything those guys say with a few grains of salt.

No need to be silly. But I do think that a degreee of better materials and/or structural designs are in order. I recall seeing an IIHS examination of a BMW seat as part of their “whiplash” testing. The seat was praised for being, in my personal opinion, very over built. There was more steel, by volume, than padding and leather. A seat like that must weigh 80lbs or more each.

You could make the seats structure out of Aluminum, again lighter and just as strong. or light still, molding CF for an even lighter and no less capable seat. Similar component fixes can be made to meet standards and reduce weigh and still give people what they want. To my knowledge most convenience electronics do not weigh that much and in most cases can be dumbed down to a few small light modules. The McLaren F1’s nihilistic view on saving weight showed that. Jay Leno gives a go walk around his F1 and the stereo system is barely as big as a short stack of DVDs.

Use noise canceling materials that weigh less. At one point FORD was using vibration isolating foam in the hollow spaces of the frame of their Trucks to quell road noise. Last time I checked Foam did not weigh that much. Want to go high tech, use noise-canceling sound systems. It costs more but if you can replace 300 lbs of noise deadening fluff with a 15-pound device, then why not… especially when people ( in the high price portends high content luxury-sport car market) will pay for that.

the 1 series weighs 3373 with a manual trans and a little less than 10lbs more for an automatic

the new m3 motor is actually lighter than the inline 6 it is replacing

also going around the top gear test track behind a toyota prius the M3 acutally had better gas mileage than the prius

Yeah now your talking! Why stop there you can take out all the glass and just use plastic. Make the seats out of old milk crates. No HVAC system of anykind. The list goes on and on… Where do I get one? LOL I’ve said it before, it’s the freakin 21 st century! I want touch screens and voice activated, EVVVVVVVVVERYTHING! I want internet access and for those long trips I’d like to be able to tell the car to take over while I watch the movie I’m currently downloading!

2006 M3 curb weight = 3,415

2008 M3 curb weight = 3,704

I know a hell of a lot about BMWs; my first race car was a 1987 320i and I’ve helped two teams turn 2002s and 320is into SCCA-class rally cars. The overall drivetrain weight of the 2007-09 M3 DID increase; the engine itself is 33lbs lighter (which, in car terms, is the weight of 3.8 gallons of gas) but the changed accessories and drivetrain add much more weight. That’s what you get for believing what the brochure tells you. And 61vette, you MADE my point, not disagreed with it — consumers have driven the bloat in weight by demanding more, more, more stuff that has less and less to do with the driving experience of the car.

I’m not defending the CAFE standards, I totally agree that measuring cars by their footprint is an idiotic method. CAFE is still engineered to let trucks and haulers off the hook, so that big business doesn’t come crashing down.

Beyond that, stripping down a car will make it lighter. But the consumer has demanded that it needs more, and the manufacturers give it to them – how else are they going to sell their product? Safety standards do play a part in how much our cars have added weight – think airbags for one. And exotic materials may help, but I’m not sure where you guys are getting your info, but everything tells me that aluminum and carbon fiber (2 examples) are actually more expensive to manufacture – somebody please show me differently.

Look, these standards are insane. They’re based on a footprint? Who thought of that one? Smaller cars actually get penalized, and big ones benefit. Does that make sense with what they are supposed to stop – big, heavy cars using a lot of gas? No car manufacturer likes the new regs. Even Toyota scoffed at the idea before it flopped back over to save its PR ass. We’ll get cars to meet these standards in 10 years, there’s no doubt about that. But we’ll also pay for it, and then we’ll have something more to bitch about.

We do need lighter cars; the race and supercar industries have shown the way to accomplish this, although automakers will never go to carbon fiber for mass production, it is just too tricky to handle on an automated factory floor. The Smart car uses a tube frame similar to a sand rail or dune buggy, and saves tons of weight that way.

But If BMW was serious about making the grade, then try building lighter cars. the BMW 1series tips the scales at near 3700lbs… and this is a car that is the size of a HONDA Civic.

Kagon (#4), you can build a large car that weighs less than 3000lbs, and get good gas mileage, pass the IIHS crash tests and get good gas mileage according to the AAA, who are much stricter and realistic than the EPA. All that and more without raising costs.

First, stop making the cars larger. Twenty years ago you could clearly tell what size-class a car was. but today the Civic, which is still classed as a Small car is nearly as big as a mid-sized car. Smaller car is instantly lighter, right? No (See BMW 1-seires), but it makes it easier to be lighter.

Next, use better materials, higher quality steel that is stronger so you use less of it so the vehicle is lighter. US more Aluminum that is as strong as stell and half the weight.

RMI, Rocky Mountain Inistitute (Go figure), put forth a car project, the Hyper Car, that makes as extensive a use of Carbon fiber as the most expensive of super sports cars, yet would cost today are $45,000 and could come down to the mid $30Ks in a few years. Carbon Fiber that weighs a small fraction of steel, is structural as strong and can be made to spring not just crumple, protecting with much less weight and/or less (by volume) material. This is a different Carbon Fiber that could easy be made to with stand collisions that would destroy a metal structure.

After seeing some Super cars crash and take nearly zero internal damage, I’m confident that a car made mostly or entirely of CF would be safe. A 3700lb car would weigh easily 1800lbs or less.

The only issue is that these companies are not making the effort and if they do it is just to grab attention and they have no intention of bringing it to market.

Next better powertrains. I am a fan of the Serial Hybrid platform. Pure electric is still decades off as far as I’m concerned as is Hydrogen. Smaller engine, making less power, instant gas safer. You will have to bolt a generator to that engine to provide electrical power for the motor(s). It could be as basic as dropping the larger engine and transmission for a smaller engine and generator and an electric motor. Some fairly straightforward electronics to control speed, and you are set to build a 100mpg car without being too exotic or expensive. To don’t even need batteries beyond the starter battery.

Nah, there are options. These companies are just too comfortable churning out the same old “same old in a funky new shell”. If they don’t wanna play, then they better hope that they don’t go out of business or be bought up when some new company shows up ready to play the new game, or an older company decides to stop bitching and just do it.