Re: Shpuker,
A lot of extra weight comes with a bigger motor and heavier components to deal with the added torque. And when comparing the Impala V6 to the Altima 4-cyl (which uses a fairly large 2500cc unit) you say the Impala gets better mileage - how do you arrive at this? You mean the highway mileage being 1 mpg better, because if you're referring to the city the Altima still handily out-miles the Impala by a hefty 3 mpg. So if we were proper nerdy mathematicians here, we would combine the numbers and divide to arrive at averages, in which the Altima would still be ahead, even with the biggest 4-cylinder of the group. And as far as the weight, well, that only better explains the proper engineering of the Altima, there's no need for a family sedan to weigh nearly two tons...