2013 Nissan Altima 2.5 SV

Sure, the V-6 makes more horsepower – 270 horses to the 2.5-liter four-cylinder's 182 – but you pay for that extra muscle in ways big and small. For one, you give up six miles per gallon, and that's significant – the EPA figures the V-6 will cost you an extra $400 a year in fuel alone. Meanwhile, the four-cylinder car is a couple hundred pounds lighter, and that weight comes off the front end, nudging the overall balance 2 percent in the right direction. And since both motors use a CVT transmission, which tends to keep revs low, you probably won't notice the difference in power anyway. I love horsepower, but in this case, light weight and efficiency trump raw muscle. [$24,460; nissan.com]