Accelerate Rapidly for Better Gas Mileage
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From: New York, NY
My Ride: '05 545i - scheduled for ED pickup in Munich on 7/22!
Yeah I learned about this concept when I got my first BMW a few years back.
Thanks for reminding me of this concept.
Now all I need is for those NYC cabs to get outta my way...
Thanks for reminding me of this concept.
Now all I need is for those NYC cabs to get outta my way...
Originally Posted by nupe009' post='228490' date='Jan 23 2006, 05:39 PM
How many miles per gallon are you guys getting based on the display in your car?
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From: Canada
My Ride: 530i, Silver Grey, Black Dakota, Steptronic, Premium, PDC, Logic7
Makes sense that you would get improved efficiency by operating at the highest efficiency point of the motor.
However, what really saps fuel economy is the slow down - speed up cycle. If you are braking (either with the brakes or engine) then you are converting some of the kinetic energy of your car into heat (hence losing efficiency). To get improved fuel economy, you need to get up to speed and then not have to slam on the brakes right away because you have caught up to the dork in front of you who is going slower than you want to. I'd say that happens about 90% of the time for me.
However, what really saps fuel economy is the slow down - speed up cycle. If you are braking (either with the brakes or engine) then you are converting some of the kinetic energy of your car into heat (hence losing efficiency). To get improved fuel economy, you need to get up to speed and then not have to slam on the brakes right away because you have caught up to the dork in front of you who is going slower than you want to. I'd say that happens about 90% of the time for me.
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From: Austin TX
My Ride: 2014 X5 xDrive 5.0 M Package Carbon Black Metallic/2008 M Roadster Imola Red
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Joined: Aug 2005
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From: Houston, Texas
My Ride: 2005 BMW 545i, Silver Grey, Sport Package, R. Shades, Cold Pkg, Sat. Rad., Prem. Sound.
You are very welcome.
I get about 16.5 when my average MPH is about 30. I suggest we all post our average MPH values when giving MPH for comparability.
[/quote]
I get 19.6 mpg with average of 34.6 mph. I drive mostly in D mode.
Originally Posted by nupe009' post='228490' date='Jan 23 2006, 05:39 PM
How many miles per gallon are you guys getting based on the display in your car?
[/quote]
I get 19.6 mpg with average of 34.6 mph. I drive mostly in D mode.
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From: Austin TX
My Ride: 2014 X5 xDrive 5.0 M Package Carbon Black Metallic/2008 M Roadster Imola Red
Originally Posted by Bimmer32' post='229179' date='Jan 24 2006, 10:58 PM
I get 19.6 mpg with average of 34.6 mph. I drive mostly in D mode.
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From: Chicago
My Ride: #1: 2004 545i; 6-speed manual; Sport Package; Mystic Blue with a gray leather interior and Anthracite wood; CWP; Logic 7.
#2: 2010 535xi Touring; Automatic.
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From: Austin TX
My Ride: 2014 X5 xDrive 5.0 M Package Carbon Black Metallic/2008 M Roadster Imola Red
....his exhaust mod...guessin he likes to hear it howl in higher gears while crusin' 
[/quote]Right, B&B muffler. Actually, when curising below 2k the B&B sometimes yields more resonance than I want especially if accelerating a bit. So, when below 2k, especially, I tend to drive in M5 because the B&B is very quiet and resonance free in M5 when crusing at low RPM. No howling unless one hits the floor and, then, you are going pretty fast so wind noise muffles the exaust sound significantly.

[/quote]Right, B&B muffler. Actually, when curising below 2k the B&B sometimes yields more resonance than I want especially if accelerating a bit. So, when below 2k, especially, I tend to drive in M5 because the B&B is very quiet and resonance free in M5 when crusing at low RPM. No howling unless one hits the floor and, then, you are going pretty fast so wind noise muffles the exaust sound significantly.


