Hackish: Leveraging the low BSFC of high-load, relatively low RPM pulses followed by engine-off gliding is the standard operating procedure for almost every fuel economy competition. (From the Shell one that's been going on for decades which was begun by the company's engineers, to the ones that members here parcipate in.)
Hang on a sec, and I'll go dig up another automotive engineer's account of why P&G works better than steady cruise at the same average speed.
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edit: here it is...
Dr Andrew Frank is (was? still is?) a PHD engineering prof at UC. Davis. This is a quote from an early 90's Motor Trend article where Prof. Davis and some of his students demonstrate the "competition" technique, which they call "burn and coast", to the writer.
Quote:
Spark-ignition engines are most efficient when run at either full throttle or turned off. What with aerodynamic drag so sensitive to speed, burn-and-coast is primarily useful at low speeds, and what do you know but the contest rules require a minimum average speed of 15 mph.
That's the bogey: Floor it up to, say, 25 mph, switch off and then coast -- seemingly forever -- down to a slow walking pace and then repeat the process. [...]
Burn-and-coast might seem a little impractical, but Dr. Frank and his students are adamant supporters.
"In Calcutta, all the taxis drive this way. It's economical, but total chaos," Dr. Frank laughs.
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They conducted a controlled comparison using 2 vehicles:
Honda Civic VX (Cali emissions)
93 mpg (US) @ 20 mph cruise
104.8 mpg (US) pulse & glide @ 20 mpg avg speed
Geo Metro XFi
84.1 mpg (US) @ 20 mph cruise
116.6 mpg (US) pulse & glide @ 20 mpg avg speed
(And just a note: the writer got it wrong where he said "full throttle" in the above quote. You can bet that Dr. Frank and/or his students said "near full throttle".)