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Quote:
Originally Posted by rusnak View Post
Totally spurious experiment. The little beaker is fuel to start a warm engine one time. The large one is fuel used idling an engine for 90 mins. A genuine exhibit would show almost the same amount of fuel in each, because the fuel needed to start an engine in 90 minutes of driving would be about the same as idling for 90 mins. In other words, you would multiply the small fuel sample by about 30 to 40 times. Their own experiment showed that starting and stopping saves about 8% fuel, but they are not doing a blind test and have skewed the results.
Mathematically what you're saying would only work out if the engine stopped for seven seconds every repeatedly for 90 mins... So, 7 seconds off, one second on for 90 minutes (neglecting the 1 second it ran, because im not going to back calculate the total time of the experiment to account for this). The fuel needed to start looks bigger graphically because it's in a much smaller cylinder. If it was in the same size cylinder it would be too hard to see. Probably should have used the same size graduated cylinder regardless to prove the point. Obviously the longer the period the engine stays stopped for, the more efficient the technology is.

The might have screwed up the driving part of the experiment... I also think they should have done it several times with the drivers switching between the cars. I guarantee you I would score lower economy that what ever green peace idiot they used in the other car even if I had the start stop. I always rack up the lowest possible mileage in any car that I own vs. the manufacturer's rating because I use a lot of throttle when I drive.
Old 08-08-2019, 10:23 AM
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