With the recent gas prices spiralling have been doing a non scientific experiment to find out how much driving habits can change the fuel economy. Reading those news about people getting 50 mpg in a regular four banger Accord makes you think how do people claim this surreal number. Is it true or it is a banal trick played by the import humpers. Websites like these Gas Savers make me try to validate this claim.
So here goes my experiment. I will just give the data, you folks decide what to claim from it.
The Precursors:
1. I keep a pretty close if not up to the decimal tab on my fuel economy numbers. For the previous miles, before the experiment, my three cars have averaged as follows.
a. 1998 Lumina City: 22.3 mpg (+-1.1)
b. 2003 Corvette Z06: 21.2 mpg (+-0.5)
c. 2005 TSX 6-speed: 26.1 mpg (+-1.5)
2. The current experiment was conducted on one tank of gas for each of the vehicles, as per the fuel I use. (Mid grade for Lumi and Premium for the other two).
3. I pretty much followed the instructions of the gassavers.org website. My goal was to drive with as light foot as possible, without speeding, and coast to the signal. But at the same time, I wanted to not to impede traffic, or cause any driving problems by excessively slow driving.
4. All three cars have had their services done within 1000 miles of the experiment.
5. I did not add any fuel additives, nor any drag prevention or aerodynamics technique.
6. All my cars are bone stock, with no mods, what so ever.
7. I have a general idea of how the lights operate on my way, and thus know when to coast and when to accelerate.
The Procedure.
1. I drive 7.5 miles one way to work. It takes me about 14 minutes, by my regular driving to drive back and forth to work.
2. All the three cars were topped to the limit (just enough to see the gas coming out of the protective flap.
3. The gas was refilled about at the time when the fuel light came on. Or the arrow passed the red dashed lines on the fuel indicator.
4. For the manual transmission cars, I passed the gears in sixth in as few changes as possible. For the vette, the 1-4 shift was used, followed by the shift in the sixth gear at about 25 mph. For the TSX I usually passed from 1-3-6.
5. The time of travel was noted.
6. I tried to avoid interstates, and expressways.
7. Experiment conducted also included my travel to the groceries, restaurants, errands and other stuff.
Results:
Following is the general summary of the three cars
Car Lumi Cori Tara
Start Day 5-May 6-May 3-May
End Day 31-May 2-Jun 4-Jun
Days 26 27 32
Miles 359.8 421.3 524.9
Refill (Gallons) 14.8 16.5 16.2
Avg. mpg 24.3 25.5 32.4
Average Time* 15.8 15.4 16.1
% Gain 8.96 20.28 24.14
Miles/Day 13.8 15.6 16.4
* Calculated for Work only. Total miles 1306 My Cafe (27.5)
General Results:
1. On an average the fuel economy went up by about 4.3 mpg, (18.5%) by my defensive driving. The average time increased by about 1.5 minutes or about 10%. That is not a significant number considering it is well within my driving limits or regular driving.
2. It seems like the manual transmissions offered a better control over the automatic.
3. Those numbers are no way near what those geezers claim.
Now Let the discussion begin.