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      06-08-2012, 01:35 PM   #83
Red Bread
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Drives: My wife's car
Join Date: Oct 2008
Location: Dallas, TX

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Quote:
Originally Posted by csween86 View Post
Sorry i seem to think this an american post a lot of times, and i talk as if im speaking only to Americans. I Lived in Germany for three years and saw a lot of Europe, so yes I know that most people drive manual, and yes most shitty and small busses there use manuals too, buts it's opposite in the US. In Europe most would love an auto because there is so much traffic, especially "staus" in Germany that people just don't want to deal with manuals anymore. But i do not agree with you on the saving fuel by jumping from 2nd to 7th. By jumping to 7th you're either under revving and forcing the engine to work harder to get up to speed, or revving high early on to satisfy 7th gear revs thus burning more gas compared to just gradually and conservatively building up the rpms. Run through each gear to its optimal rpm range and you will get best gas mileage.
Regardless of torque, a motor is most efficient at larger throttle openings and lower revs than smaller throttle openings and higher revs. There's a reason that GM uses the 1-4 skip shift on their six speed manuals. In city driving, I'll frequently use 1-3-5 and get 2-3 mpg better than if I use each gear.

Similar logic applies to my wife's 135i slushbox which shifts below 2k rpm every time, unless it's in DS. Using your theory of shifting where the torque and power curves cross, around 5.2k rpm with the N54, she'd probably get single digit mpg.

Funny thing is that while working in Germany for four years, I think all but one of my colleagues drove manual cars, and most skipped gears.
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