BMW needs to use it engineering ability to design cars that use less gas.

[COLOR=Green]BMW needs to use it engineering ability to design cars that use less gas.


My brother Honda mini van has a V6 engine that shuts down cylinders when at a low load highway speed; why can’t my BMW V8 do that?

My BMW down shifts to fast such that the car will not roll to a stop. The trans should be programmed to stay in a higher gear unless its in sport mod.

Performance and fuel economy are not mutually exclusive and BMW should be leading the way. [/COLOR]

I agree, cars are getting to be so fast that more power isn't necessarily what I want more of (of course it's always nice). I think better fuel economy interests me more.

They already do, Bmw makes some of the finest diesel engines available...

My 530D uses about 7.2 liters on the highway, I reckon that's around 38-39 mpg...not bad at all....

That would be nice. Cylinder deactivation (or GM's displacement on demand) is an old technology first found in Mercedes, Caddies, and now re-introduced by GM, Dodge/Chrysler, and obviously...Honda. With cylinder deactivation, you can save roughly up to 20 to 30% in fuel economy by disabling cylinders when crusing, but then you start to introduce noisy harmonic vibrations...from when you have V6 running on 3 cylinders (an uneven combustion cycle). To counteract this, you have to add counter rotating balancing shafts (which adds rotational mass and reduces engine performance) to smooth out the V6 or V8, a sound dampening system or active noise cancellation technology...which adds more complexity and weight, and the throttle would have to be electronically controlled...so that when you step on the accelerator you won't have a lumpy ride from going from 3 cyclinders back to 6 cylinders. In the end, the gains are minimal...and BMW would have to spend more on R&D to implement all that technology...and make the cost of owning our Beamers even more.

James

Originally Posted by Oomer

That would be nice. Cylinder deactivation (or GM's displacement on demand) is an old technology first found in Mercedes, Caddies, and now re-introduced by GM, Dodge/Chrysler, and obviously...Honda. With cylinder deactivation, you can save roughly up to 20 to 30% in fuel economy by disabling cylinders when crusing, but then you start to introduce noisy harmonic vibrations...from when you have V6 running on 3 cylinders (an uneven combustion cycle). To counteract this, you have to add counter rotating balancing shafts (which adds rotational mass and reduces engine performance) to smooth out the V6 or V8, a sound dampening system or active noise cancellation technology...which adds more complexity and weight, and the throttle would have to be electronically controlled...so that when you step on the accelerator you won't have a lumpy ride from going from 3 cyclinders back to 6 cylinders. In the end, the gains are minimal...and BMW would have to spend more on R&D to implement all that technology...and make the cost of owning our Beamers even more.

James

James what are saying Honda can do it but it would cost to much for BMW to do it.
People used to think that emision control and computers were bad; with logich we still would be getting 10 miles to the gallon and producing tons of pollution. Do you still drive a 1975 BMW?

You can't be serious??

You're driving around in a performance oriented V8 SUV and you expect fuel efficiency?

I just don't get it.

Yes I drive a V8 sav. It get about 19 mile to the gallon, not that much less than your 325I.

That does not mean BMW should make improvements.


The changes I sugested would have little or no impact on the driveablity.

Originally Posted by alpinewhite325i

You can't be serious??

You're driving around in a performance oriented V8 SUV and you expect fuel efficiency?

I just don't get it.

Yeah, I gotta agree.

Besides, compared to other manufacturers, BMW already does a pretty decent job regarding fuel economy. And I'm certain it will be in BMW's best interest to stay somewhat competitive with their efficiency standards, as this is a huge issue for many consumers.

I think they are making good progress.

My 6 series gets about 19 city, 26 highway mpg. This is the same mileage my 330 E46 convertible got. So the 8 cyclinder with 325HP and the lighter materials ensure good performance while being mindful of fuel consumption.

A big part of fuel enconomy is government regulations. Unless the governent raises the fuel economy standards, manufacturers won't improve much. Not because they can't or won't but to remain competitive. If they voluntarily increased fuel enconomy and reduced performance, and their competitors did not, there would be a uneven playing field when selling cars.

The gains we see in fuel enconomy have always be modest in my view.

I thought we would all be driving electric cars by now.

Originally Posted by mandrake203

Yeah, I gotta agree.

Besides, compared to other manufacturers, BMW already does a pretty decent job regarding fuel economy. And I'm certain it will be in BMW's best interest to stay somewhat competitive with their efficiency standards, as this is a huge issue for many consumers.

Originally Posted by x54.4blue

BMW needs to use it engineering ability to design cars that use less gas.


My brother Honda mini van has a V6 engine that shuts down cylinders when at a low load highway speed; why can’t my BMW V8 do that?

My BMW down shifts to fast such that the car will not roll to a stop. The trans should be programmed to stay in a higher gear unless its in sport mod.

Performance and fuel economy are not mutually exclusive and BMW should be leading the way.

I disagree with you. BMW makes sporty cars, even its X cars. They could be made to perform exactly like Hondas but then . . . they would be Hondas! And then you wouldn't have a choice.

You need to buy a Prius or alternative hybrid vehicle. I'm sure you'll find contentment with the FWD pull while still being sensitive to mother earth.

Some others may just want to tear ass leaving skidmarks on the planet!

To each their own, but choose play in the right sandbox.

p.s. Boldface and large type uses excess energy. Save the planet, take your meds.

Did a small test today as I drove from Birmingham AL to Knoxville TN. Roughly 250 miles. Set the cruise control at approx 75mph most of the way on 6th gear. Ended up with 30.5mpg on 93 octane fuel. I used slightly less than half the tank (as per the indicator) for the trip.

Not bad!

Originally Posted by x54.4blue

BMW needs to use it engineering ability to design cars that use less gas.


My brother Honda mini van has a V6 engine that shuts down cylinders when at a low load highway speed; why can’t my BMW V8 do that?

My BMW down shifts to fast such that the car will not roll to a stop. The trans should be programmed to stay in a higher gear unless its in sport mod.

Performance and fuel economy are not mutually exclusive and BMW should be leading the way.

BMW already does a lot to save gas. Have you compared your 4.4 x5 against its competitors(mercedes,lexus,porsche,infiniti), it leads them all in gas mileage. Why would BMW waste time and money(assuming it requires this) on something that is already class leading and not even a major concern. First of all this is an expensive luxury car and I don't think most people are going to be overly concerned. Second it's an SUV/SAV so people buying this type of vehicle already know what to expect. How are you going to compare this with a Honda when it's not even in the same class. I think some people just expect too much out of BMW.

I think it would be more helpful to the world if you leaned how to type in a normal size font


BMW is as good or better than the competition in fuel mileage, I can get 30 MPG on the freeway in my 325 or Z4.

If you gave a crap about fuel economy you wouldn't have bought that silly tank the X5

Originally Posted by x54.4blue

My brother Honda mini van has a V6 engine that shuts down cylinders when at a low load highway speed; why can’t my BMW V8 do that?

My BMW down shifts to fast such that the car will not roll to a stop. The trans should be programmed to stay in a higher gear unless its in sport mod.

Performance and fuel economy are not mutually exclusive and BMW should be leading the way.

Why did you buy a 6,000-lb. vehicle if you were going for performance or fuel economy?

Most automatics don't roll to a stop when in Drive because of the torque converter.

If you're driving an '04+ X5, you have the 4.4-liter V-8 featuring Valvetronic, which is a BMW innovation that gets you performance and better fuel economy. The short of it is it reduces pumping losses, the same thing shutting off cylinders reduces. BMW's solution would seem to avoid cylinder deactivation's problems, which are uneven cooling and balance issues (vibration).

An '04 X5 4.4 is EPA rated 16/22 mpg. Compare that to the previous generation V-8 getting 14/18. Compare that to the 3.0-liter M54 inline-6's 16/21 mpg (for X5 automatics). You're getting 90 more hp and comparable fuel economy than an engine that is 2/3 the displacement.

That Honda minivan is rated for 19/25 but weighs 1500 pounds less. What kind of magical non-compromise vehicle are you expecting??

Originally Posted by chuck92103

A big part of fuel enconomy is government regulations. Unless the governent raises the fuel economy standards, manufacturers won't improve much. Not because they can't or won't but to remain competitive. If they voluntarily increased fuel enconomy and reduced performance, and their competitors did not, there would be a uneven playing field when selling cars.

That's what CAFE is (government regulation that sets increasing economy standards for a manufacturer's product fleet).

CAFE Summary (2005 scores are on page 7)

Originally Posted by chuck92103

...The gains we see in fuel enconomy have always be modest in my view.

I thought we would all be driving electric cars by now.

***fantasizes about a future with all-electric BMWs, including the all-new year 2025 BMW 3-series line up: 350kWi, 375kWi, and M3kW***

Technical Data:

350kWi: 50 kilowatt NiMH Voltronic, 67 horsepower, 0-60 in 25 seconds, top speed 75 MPH
375kWi: 75 kilowatt NiMH Voltronic, 100 horsepower, 0-60 in 16 seconds, top speed 90 MPH
M3kW: 155 kilowatt Li-ION Voltronic, 234 horsepower, 0-60 in 7.2 seconds, top speed 145 MPH

Scary, huh?

Originally Posted by PotatoAddict

350kWi: 50 kilowatt NiMH Voltronic, 67 horsepower, 0-60 in 25 seconds, top speed 75 MPH
375kWi: 75 kilowatt NiMH Voltronic, 100 horsepower, 0-60 in 16 seconds, top speed 90 MPH
M3kW: 155 kilowatt Li-ION Voltronic, 234 horsepower, 0-60 in 7.2 seconds, top speed 145 MPH

A little Googling says electric traction motors are rated at continuous output, not peak output. One page says a 30-hp electric motor is roughly equivalent to a 50-hp gasoline motor. Plus, don't forget the gobs of low-end torque.

Font problem fixed

One could argue that the Prius is just as bad on the environment. No it is not burning as much fuel. Just dumping 8 times as many lead and acid filled batteries into land fills as a regular car.

Originally Posted by Sheepdg

You need to buy a Prius or alternative hybrid vehicle. I'm sure you'll find contentment with the FWD pull while still being sensitive to mother earth.

Some others may just want to tear ass leaving skidmarks on the planet!

To each their own, but choose play in the right sandbox.

p.s. Boldface and large type uses excess energy. Save the planet, take your meds.

I read that most of the oil industry agrees we have approximately 100 years oof fossil fuel left. If this is true, knowing how our world works, I would not expect to see a predominance of electric vehicles for at least 30-50 more years.

So I will go to my grave with Vanna ( or is it Vanos?) oh yeah right, that is wheel of furtune .

Originally Posted by PotatoAddict

***fantasizes about a future with all-electric BMWs, including the all-new year 2025 BMW 3-series line up: 350kWi, 375kWi, and M3kW***

Technical Data:

350kWi: 50 kilowatt NiMH Voltronic, 67 horsepower, 0-60 in 25 seconds, top speed 75 MPH
375kWi: 75 kilowatt NiMH Voltronic, 100 horsepower, 0-60 in 16 seconds, top speed 90 MPH
M3kW: 155 kilowatt Li-ION Voltronic, 234 horsepower, 0-60 in 7.2 seconds, top speed 145 MPH

Scary, huh?

Doesn't the new M5 run on 8 of it's 10 cyl for 'economy' driving?

Originally Posted by MARCUS330i

Doesn't the new M5 run on 8 of it's 10 cyl for 'economy' driving?

Nope.

Interesting link

http://www.bmwworld.com/technology/valvetronic.htm

Originally Posted by x54.4blue

[[SIZE=3]COLOR=Green]BMW needs to use it engineering ability to design cars that use less gas.

My brother Honda mini van has a V6 engine that shuts down cylinders when at a low load highway speed; why can’t my BMW V8 do that?

A car with a V8 tends to be a gas guzzler; for less consumption, you have a smaller engine. What kind of mileage does your brother's minivan's Honda's V6's engine get? Is it better than the 40+ mpg routinely available from a 320d or 530d (saloon, touring, you choose)?

A couple of US-style V8s have been introduced to the UK recently purporting to have "normal"-style fuel consumption. One car, the Pontiac GTO, has a 6 litre engine whose manufacturers (Holden, though the engine comes from GM Powertrain in the US) say the engine is so big that at low speeds its more parsimonious than an econobox redlining, apparently, to keep up with our traffic. It got 19 mpg on the touring cycle in one road test. The other, a Chrysler 300 V8, got 17 mpg, despite its trick shut-down technology. Neither, it seems, has yet to hit the sweet spot