Posted by Trixter on July 23, 2007
In 2001 at the height of the internet bubble, I sold stock options to pay for a minivan for Melissa. I knew she liked to have the air conditioning on all the time, and we needed to merge onto the highway a few times a week via a terribly-designed onramp (where you have about 1.3 seconds to merge or you will die), so I made sure the minivan had a V8 in it so she could have no problems merging onto the highway with the air conditioning on. My prior experience with doing so was in a tiny Ford Escort, which has an engine so weak that turning on the air conditioning effectively acts as a secondary braking system. I thought that getting a V8 was a good idea in this context.
Big mistake. A V6 would have been sufficient; a V8, on the other hand, guzzles gas like it’s going out of style. This wasn’t a problem when gas prices were $1.60 a gallon., but now that they’re $3.50/g, we’re spending nearly $200 a month on gas, sometimes more. For some people, this is nightly dinner money. For us, it’s the utility bill, so it hurts.
I read in a recent Slashdot post (URL escapes me at the moment, sorry) that modern cars can get nearly hybrid-like gas performance if computers were installed to learn how to coast to stoplights. Due to broken air conditioning in the van, Melissa and I have traded cars for the summer (I don’t mind the heat) and I decided to put that theory to the test in the V8 gas guzzler. Bottom line: It works, but you have to exercise discipline.
When Melissa drives the van, she drives it hard, and the average MPG is about 14mpg. I, however, have been setting cruise control to exactly the speed limit every chance I get, and coasting 100 feet or more to stoplights. My average MPG? 21mpg. Just by adjusting driving habits, I got an average of 126 more miles out of each tank; filling up the tank twice each month, that’s a savings of $42. It’s essentially one free fillup a month.
The tradeoff is that you need to be very aware of the car and the road when you do this. For example, don’t accelerate quickly to get to the speed limit, which burns all your savings in a few seconds; instead, try to keep your engine’s RPMs under 2000 no matter what. (Warning: This may piss off the people behind you.) Also, constantly scan far ahead to anticipate how early to cancel cruise control — too late, and you miss out on gas savings; too early, and you’ll be coasting up to the stoplight for nearly a full minute. (Warning: this will piss off the people behind you.)