Gas upgrade pricing
Nerdishness comes in many forms, and a certain electrical enginerd friend has got the equations to prove it. His observation: “Since the 10 cent difference between each grade is constant, as gas gets more expensive, that extra 10 cents per gallon makes less of a difference.”
As gas prices go up, the percent increase in gas mileage is unaffected, but the “upgrade fee” for the premium grades goes down. There’s a simple formula and explanation based on your car’s habits and current prices that will let you know if it’s worth the jump. He notes that “the worse your overall gas mileage is, the more potential you have to save money by buying the right grade.”
We’re still getting relief on the “downgrade pricing” as E85 fuel is around $2.00/gal. here. So we get a 25-30% drop in price and around 15% less mileage. But I don’t think the savings are as good in many other places around the USA.
Comment by Dad — October 10, 2007 @ 5:33 pm