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Old 10-14-2009, 10:41 PM   #18 (permalink)
MetroMPG
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Location: 1000 Islands, Ontario, Canada
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Quote:
Originally Posted by moorecomp View Post
I know my EOC distance is not as good on wet roads. Probably the biggest reason for my difference in mpg's. Anyone up for some coastdown testing? Another thing is the humidity and a lower pressure associated with a rain pattern contributes to higher density altitude, which means less efficient engine.
Ah, but some would argue the lower air density = less aerodynamic drag.

And I've read some people swear they get better MPG at altitude, with the less dense intake charge depowering the engine, requiring a wider throttle opening, reducing pumping losses and improving efficiency. Same effect could happen with low vs. high pressure at the same altitude (assuming OBD computer controlled mixture).

And I completely agree about the shorter coasting distance on wet roads.
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