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Old 12-10-2007, 07:04 PM   #7 (permalink)
EcoModding Apprentice
Join Date: Dec 2007
Location: Melbourne
Posts: 152

The Mighty Mira - '92 Daihatsu Mira
90 day: 61.32 mpg (US)
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Originally Posted by SVOboy View Post
Interesting observations indeed. Of course speed was a huge factor for my car (more so than acceleration), but I was surprised at how much difference playing with gearing at 100kmh while driving at 100kmh changed things around.
One thing I forgot to add, this assumes that we are accelerating using 62% of available power, whatever throttle that is at. Deviate too far either way and there will be FE penalties. See the BSFC graph. Pick an rpm, and vary the load on the engine. The BSFC is efficiency, lower = better.
The only problem with dedicated slows lanes is that they would have to be cross by traffic to get in/off ramps and things, where the speed difference might make things unsafe, I think.
I think this is done in Germany already. Might be better to just slow down everybody to about 50mph/80kph. I almost can't believe I'm writing this - I used to go a bit above the speed limit religiously. But that's a very good compromise speed - lions share of the benefit, and still a fast speed.
"Every body perseveres in its state of being at rest or of moving uniformly straight forward, except insofar as it is compelled to change its state by force impressed." - Isaac Newton
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