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Old 05-20-2011, 06:05 PM   #10 (permalink)
SentraSE-R
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Join Date: Jun 2009
Location: Bay Area, California
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Mean Green Toaster Machine - '06 Scion xB
Team Toyota
90 day: 48.92 mpg (US)
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That's a possible option - to put taller tires on the stock wheels. 195/65-15s would be 5% taller than stock while only weighing 37 lbs. I'll keep my eyes and ears open for used tires in that size, for a future test.

I don't follow Mark's math. Unsprung weight affects inertia and handling, but I don't see how it equals an 8% increase in the effective weight of my vehicle, nor how that necessarily affects fuel economy. I pulled 48 mpg with 600 lbs of passengers on a 150 mile drive last Fall. The added momentum on downhills pretty much made up for the extra work getting the weight up to speed.
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Darrell

Boycotting Exxon since 1989, BP since 2010
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac? George Carlin
Mean Green Toaster Machine
49.5 mpg avg over 53,000 miles. 176% of '08 EPA
Best flat drive 94.5 mpg for 10.1 mi
Longest tank 1033 km (642 mi) on 10.56 gal = 60.8 mpg

Last edited by SentraSE-R; 05-20-2011 at 06:47 PM..
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