The 2007 Porsche 911 Turbo is the first 911 to feature aluminum doors. Weighing just 24 lbs. total, they take 31 lbs. off the car’s total weight. In fact, the entire car, despite the addition of an all-wheel drive system, is 12 lbs. lighter than the previous model. At 3,495 lbs, its power-to-weight ratio is an impressive 1.4:1 or 1.4 hp per pound – that’s very close to the Ferrari F430 at 1.5:1 and the Ferrari 599 GTB at 1.6:1. That’s some pretty good company. Of course, quality cannot be expressed in power-to-weight ratios alone. After all, the Dodge Viper boasts a 1.5:1 ratio, but it’s nowhere near as sophisticated as the Ferraris and the Porsche. For instance, despite the new 911 Turbo’s wider dimensions and larger wheels, Porsche managed to retain the drag coefficient of the previous 911 Turbo while also increasing downforce. Increased downforce keeps the tires on the road, resulting in better handling, even at higher speeds. This was accomplished by tweaking the body and trim, and adding things like a new spoiler lip on the front air dam and changing the shape of the air vents that cool the brakes and engine. This is exactly the kind of effort and attention to detail that you’d expect from one of the world’s greatest sports car makers, and helps to explain the stratospheric price tag.