Thread: where to start
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Old 03-18-2010, 11:59 AM   #30 (permalink)
gone-ot
...beats walking...
 
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Quote:
Originally Posted by laack View Post
...so warmer weather alone would account for at least 1 mpg gain.
...although this data derives from an '09 Pontiac Vibe 1.8L (DISI) with 4-speed automatic, it might provide a "closer" estimation of fuel economy versus temperature.

1) 28 data pairs [ one in morning (am) and one in afternoon (pm) each day ]
2) temp range: lowest am temp = 37°F; highest pm temp = 84°F
3) roadway: 4-lane freeway driving 95% of the time (time: 05:00 am, ~05:30 pm) 5% urban street & stoplights
4) distance each way: 26.2 miles
5) slight 0.2% road grade (altitude: 2330' home, 2550' work)
6) two rainy days, two windy days

...the linear regression equation (so far) from the data pairs:

MPG = (°F)/5 + 25

...with correlation coefficient of about: RR = 0.8-0.85

...obviously only 100% relevant to my vehicle, but might be useful as a "rough approximation" guess-ta-mation.
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