Originally posted by: giantpinkbunnyhead
Originally posted by: Atheus
Originally posted by: MS Dawn
Speeding wastes fuel (cars are horribly inefficient as it is) causes emissions to increase
Correct me if I'm wrong, but I'm pretty sure it doesn't take any more energy to keep a car moving at 100MPH than it does it does to keep it moving at 50MPH. If you're talking about simply driving fast, rather than 'racing' around (which involves large and repeated accelarations), I don't think it's more inefficient than driving slowly.
/Edit: spidey beat me to it...
Ok, to correct you... if you double your speed, you get a fourfold increase in parasite drag and induced drag. These forms of drag are caused by the shape of your rig... it's cross section, it's mirrors, antennas, whatever. in other words, drag = wind resistance. But the reason this harsh hit is diminished so much is due to the aerodynamics, gearing, and various other factors that car companies have employed. But if you do a one-for-one, all factors equal, comparison test, you'd find very different results than only losing a few mpg between, say, 50 and 100.
Another deceptive statistic is the mpg figure when comparing speeds. a gallons-per-hour would be more appropriate. This is why commercial aviation uses gph instead of mpg. It's a better gauge for engine performance. Say you got 20 mpg at both 50 and at 100 mph. You'd think no extra work is being done... but consider that at 100 mph, you'll burn through 5 gallons of gas in that hour. At 50mph, you'd only burn up 2.5 gallons of gas in that hour. In both cases your engine runs for an hour, but it required double the fuel to maintain the higher speed.