Quote:
Originally Posted by California98Civic
3-4% over OEM pressure specs is significant. That's measurable extra range.
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I've come around to agreeing with that as I have spent way too much time trying to mold numbers from the online calculator here into working with a pure EV more directly in miles per kWh in my own spreadsheet.
I figure that my i3 uses approximately an additional 150W for every mile per hour faster it travels. If the vast majority of that can be attributed to tire rolling resistance and a Crr guess of 0.007 at BMW recommended pressures, bumping it up to near max and the lowest rated rolling resistance of about 0.006 for the EP-500s nets about 21 watts saved per mile per hour.
Put another way, that's an extra 13% range at 30 mph.
The mirror delete I think I have figured a little more accurately now, likely saving about 1.0% at 65 MPH. It's closer to 0.7% at 30 MPH and 2.2% at 75 MPH if it does not improve Cd at all. I am betting however on at least a 0.01 improvement there which will pay a larger dividend.
All combined in a best-case calculation, it should be about 11.5% better at 65 MPH.
But it's time to quit estimating and making educated guesses. I need to get some serious baseline numbers with the stock mirrors before I rip the door panels off to remove them.