In the interest of science, and because I have a curious mind, I bought taller tires today. I was browsing Craigslist yesterday, and found four used Goodyear Eagle NCT 5s with 70% tread for $30 each, size 205/50-17. I've saved >$1700 hypermiling, so I don't feel guilty spending some of my savings on the frivolity of pretty wheels.
The new tire/wheel combo is 5.31% taller, 25.07" to the stocker 185/60-15s' 23.74". They turn 829.6 rpmile v. 876.1 rpmile for the stockers. So when the engine used to spin ~3000 rpm to go 60 mph, it will now spin ~2840. They rub a bit on full left turns, but so did the stock tire/wheel combo.
The stockers had a 5% speedometer error (60 mph indicated was about an actual 57 mph), but no odometer error. The new tires should correct my optimistic speedometer, with their 5.6% slower factor, and I'll need to incorporate a 5.6% odometer error.
I hope to do some ABA testing in the future.
__________________
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; 05-04-2011 at 08:27 PM..
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