Thread: 2000 rpm
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Old 02-26-2009, 07:11 AM   #19 (permalink)
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Accelerating near peak torque will usually get you the best FE. Cruising at peak torque will definitely NOT get you the best FE. To look at this we need to take speed out of the question (obviously, if you slow down your load decreases, and thus the amount of fuel needed). We need to look at a specific load and graph it on a BSFC chart. I did just this a while back in this thread.

If you take a look at a bunch of BSFC charts, you'll see that in 99% of the situations you could gain quite a bit of efficiency by lowering rpm and increasing load. I'm sure there is an exception out there somewhere, but I have yet to see it.
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