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Old 10-26-2008, 05:00 PM   #3 (permalink)
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Join Date: Jun 2008
Location: Toulouse, France
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scenic - '01 renault scenic
90 day: 43.09 mpg (US)

megane - '97 renault megane classic
90 day: 72.53 mpg (US)

dennisius - '06 Toyota Prius
Team Toyota
90 day: 69.27 mpg (US)
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Originally Posted by 07b2300 View Post
MetroMPG, I read that you were planning to test and post results--did you ever do it?
Is it what you are looking for ?

A little context: I bought low RR tires for my truck and seemed to increase FE on average about 8%, but overinflating (even to just 35 psi) only seems to help the truck ride rougher than it already does.
From placard of 33 psi, I inflated to 43 and felt a change in coasting. When inflated to 46 I felt even more difference and in city it seamed to coast forever... I inflated to sidewall of 51 yesterday evening.

I haven't had the cash to buy a scanguage yet and am determining my FE old school (like the manual recommends): miles driven divided by gallons used. While a good system for an average FE, it isn't so good for showing the effects of small mods like this.
Personally at each fill-up I calculate the saving in money, and I save that amount for investment in my cars. I already bought some anti-rain and anti-fog products, some new hubcaps, a voltmeter and a little solar panel (for the battery I had to change but that isn't totally dead, so I keep it to feed my (GPS) navigator).

So I'm wondering how much tire pressures are helping anyone else because if the effect is negligable I'm going to put it back to help keep my coffee off my lap!
As numbers from MetroMPG post are significantly different, you can guess that with the proper driving techniques (DWB and coasting) you'll get success. Changing habits do need work, but success will be significant.

Save money & CO2 at home :
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Earth and health are priceless, so are kilotank and AT-PZEV
Best Mégane tank: 1268.9mi @ 77.847 MPG(US)
2008/06-2011/10 saving:
  • 5725.5 kg CO2 (5342.6+382.9)
  • Diesel / Money: 42.17% = 2446.25€ = 3357.26$

megane : thread - kill switch.
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