The faster you drive, the more fuel you use. Common sense, right? Absolutely, but it's still helpful to see real-life data, as you'll see by checking out the results of a recent test performed by Consumer Reports. Not all cars perform the same at various speed limits, and as you might expect, America's most fuel efficient models are also the vehicles most affected by speed.
A total of seven vehicles were tested by CR: a Acura TSX with a 2.4-liter four-cylinder; a new 2010 Honda Insight; a Lexus RX350; a Mercury Mountaineer with 4.6-liter V8; Toyota Camry and RAV4 with 2.5-liter four-bangers; and a Toyota Yaris with a 1.5-liter four.
As you're probably aware, today's hybrids are optimized for high fuel economy at city speeds and therefore lose much of their miserly ways on the highway. As it turns out, this was especially true of the new Insight hybrid, which lost over 15 miles per gallon moving the needle from 55 mph to 75 mph – the largest drop in the contest. Click here for the complete test results.