|01-23-2013 09:01 AM|
Today I drove my usual 4.1km to work. The temperature outside was -19 degrees Celsius.
When I started my car the distance to empty was 401km. When I got to work the distance to empty was 380km! (When I fill up to max, distance to empty is 540km)
Now I always found the distance to empty was a pretty accurate number as it seemed to be tailored for city driving. For example, when I drive 120km (90% highway) to visit family, the distance to empty goes down at max 80km.
Is there any tips you guys have to improve winter fuel economy?
|12-07-2012 11:17 AM|
|12-06-2012 06:23 AM|
|MelloYelloTi||Last 2 tanks have averaged to about 27 to 28 mpg overall. Down about 4 mpg from about a month ago. Still not to bad as my Sable was getting 16 to 17 mpg overall in the same temps..|
|12-03-2012 10:17 PM|
In highly idealized situation if the air pressure happens to be the same at two different temperatures, then the new velocity is simply the original velocity times the square root of the new temperature divided by the square root of the original temperature. (Use absolute temperatures in the calculation)
For instance, if a vehicle is traveling 70 mph at 70F, then it experiences the same amount of form drag at 67.3 mph at 30F.
|12-03-2012 07:48 PM|
I reran the calc and it said the 16s would now read 2.1% fast. That's pretty negligible IMO (ie, actual speed is 100 km/h but speedo reads 102).
The 18s are way too fat for this car, but they are awesome. My fuel eco definitely is better with the skinnier winter tires on (while it's still not actually winter yet, most days are above freezing still). Maybe when the 18s wear out I might pick up some factory 17s, just to have a hope at actually getting 40 mpg for once :p
|12-03-2012 12:58 PM|
Don't forget that tire pressure will drop a bit with temperature too. Not sure exactly how much it will drop, but I found a reference that it is about 1psi / 10 degrees F.
So if you inflated them at 70F, they will be 3-4 psi lower at 32F. That can cause a noticeable drop to gas mileage.
|12-03-2012 12:05 PM|
I've gone thru 7 winters in massachusetts, and drive the same commute each day, with little weekend travel. My commute is not highway, but I can go 45-50 most of the time, with few stops and slowdowns. Summer I get a consistant 30-31 mpg, winter consistant 27-28, like clockwork.
The cold effects in several ways. All fluids (oil and grease) are thicker so offer resistance. Tire pressure goes down, if you haven't checked it. My previous Eclipse with awd, in summer backing up out of the drive, clutch in, it would coast. In winter, definitely stop coasting much quicker.
Gas gets vaporized poorer so less efficient burn (regardless of electronics), engine warm up even if you start off rightaway, traffic slowdowns.
The change from summer to winter gas is mostly to ease vaporization, and I can't believe the little power difference would make much difference
|12-03-2012 10:18 AM|
There would be about a 6% increase with the smaller tires.
In other words if you traveled 100 miles your odometer would actually show 106 miles.
It actually says 5.833%, which @ 30mpg would show as a 1.7mpg increase.
That is just what that site says, I do not actually know how to do any of the tire size calculations.
|12-03-2012 09:57 AM|
|12-03-2012 09:41 AM|
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