Lighter, Stiffer, More Aluminum und Steel
Making more extensive use of aluminum has allowed the newest 911 is both lighter and stiffer than the 997. Neither weight nor stiffness are game-changers, however. They are simply incremental improvements that show their worth at the limit.
Porsche says almost 90 percent of the 991's parts are redesigned or redeveloped. The smaller, more potent engines alone account for a significant portion of the redesign, revving quickly and yet sipping fuel--a design goal aided by the lighter body and chassis.
The stiffness, on the other hand, helps get the most out of the re-tuned suspension, which keeps the 991 flatter in the turns than the 997 while ironing out the bucking Southern California pavement at the same time.
Three driver-selectable suspension modes help with that balance: normal, Sport, and Sport Plus. With all of the buttons in the off position, the 991 is smooth and pliable for the most part, and a willing commuter. Kick it up to Sport and the finer bumps will be more pronounced, though even on Sport Plus, those accustomed to taut, focused sports cars will find the ride acceptable.
With each incremental step toward Sport Plus, handling becomes sharper, throttle response more focused, and, when the magic exhaust button is pushed (it can be operated in any of the three modes) the car's throaty exhaust roars just a bit brighter. The slight crackle on overrun, and the searing howl as it approaches the 7,500-plus rpm redline, are sheer pleasure.
Auto Stop-Start, Idle on Coast: A Greener 911
The level of technology packed into the 991 is impressive from an engineering and packaging standpoint alone, but it also forms a synergistic system that helps the driver extract more enjoyment from the experience.
Auto stop-start (standard only on PDK-equipped cars) might not sound like much fun, and in truth, it's not, but it is a welcome fuel-saver when stuck in stop-and-go traffic, and it's so seamlessly implemented that you'll have no reason to complain about it. It just works.
It also works in combination with another PDK-enabled fuel-saving technology: let off the throttle while cruising around town or on the highway, and the engine will fall to idle while the car coasts. If you want to manually enable the coast function, you can just give the upshift paddle two quick tugs. Instant fuel savings, whenever you like. Get back on the gas and you'll accelerate off into the distance without the slightest hesitation. Again, it just works.
These features, along with the redesigned engines and a litany of other small tweaks enable the 2012 Porsche 911 to reach up around the 30 mpg mark on the highway, according to the company's European testing. The EPA's testeing is likely to show poorer numbers, but real-world driving will benefit immensely from the auto-stop start and coast functions.