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Old 07-28-2008, 06:14 PM   #8 (permalink)
Box Dreamer
Join Date: Jul 2008
Location: Pittsburg, CA
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xB Commuter - '04 Scion xB
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Originally Posted by PaleMelanesian View Post
The correct rpm is usually "lower".

For context, the Honda Insight runs at about 1950 rpm at 60mph. That's with a 63hp engine. Any larger engine should be able to run at even lower rpm to produce the same power.
FYI, Insight runs that low rpm because IMA gives boost if needed. Without IMA, running such low rpm in small engine doesn't have enough power to pass other cars on highway. That is why Civic runs higher rpm even the engine is bigger. Generally, bigger engine usually cruise with lower rpm for the same reason. Just using insight as an example is not appreciate.

Another observation we see from insight engine is lean burn happens in low rpm. Running less than 2krpm at 60mph saves more gas on highway.
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