Porsche has nearly finished introducing the last of its myriad variants of the current-generation 911, known as the 991.2. Since that process takes the better part of seven years, that means it's just about time for a new generation. Dubbed the 992, it's a significant move from the 991 generation that was introduced for 2012, with evolutionary changes in styling and to the chassis and more significant alterations to the interior and the powertrain. EDITOR'S NOTE: You're reading a story by American title Car and Driver. We're bringing you a handful of C/D stories each month, focused on vehicles we've either not yet driven, or models not offered in Australia. Where appropriate, we'll add metric measurements for reference, but grammar and terminology will otherwise remain unchanged. The styling and chassis changes are closely related, as all 992s will have the wide rear bodywork that currently is used only on the all-wheel-drive and GTS models.
This means that all versions will have the voluptuous 72.0-inch-wide (1828mm) hips in the back, and these will be coupled to a 1.6-inch-wider (41mm) front track with matching wider front fenders. The wheelbase is unchanged, but overall length grows by about an inch鈥攁ll in the front overhang鈥攄ue to a more rounded nose. The Carrera S models that we rode in wore Pirelli P Zero tires in sizes 245/35 R20 in front and 305/30 R21 in the rear. That's the same front tire size as today's cars, and the rears share section width and series, so they're exactly one inch larger in diameter than the 991's rear tires and raise the rear axle height by half an inch. According to August Achleitner, Porsche's VP of sports cars, the larger rear tires increase the contact patch. The wider front track builds on this by reducing the load transfer from the inside to the outside tires during cornering. This essentially means greater front roll stiffness without resorting to a stiffer anti-roll bar.
Those wider rear fenders are now stamped in aluminum, replacing one of the few steel exterior panels on the 991, for a weight savings of between 22 and 33 pounds. The 992 also has flush door handles that extend when you touch them. These exhaust tips are not physically connected to the muffler exits, which allows them to be closer to the fascia鈥攁t the price of some authenticity. This disconnection also reduces repair costs in rear-end collisions, which apparently is important for German insurance premiums. A larger active rear spoiler extends beyond the width of the engine cover to the outer edges of the taillights. Achleitner says that it produces slightly more downforce than the 991's wing, reducing overall lift to zero, while the current car has a small amount of lift even with the spoiler deployed. Drag coefficient for the Carrera S is said to be 0.29, reduced from 0.30, but offsetting that is the greater frontal area due to the wider fenders and the height increase.
Under the new skin, the structure and suspension of the 992 is similar to that of the 991. Perhaps the biggest change is a new engine-mounting system. In previous 911s, there has always been a beam bolted to the back of the engine, which attached to the outboard motor mounts. Such widely spaced mounts could be soft while still limiting engine motion. The 992's rear mounts are on the engine's cylinder heads, closer together and forward of the traditional setup. This gets those mounts closer to the main rear structure of the car, stiffening the entire rear assembly and also saving a bit of weight. One new standard feature is an advanced Wet driving mode. Wet pavement is detected by what is essentially a parking-distance sensor placed in a front wheel well, and it determines when the pavement is wet based on spray from the tire. When the car detects pavement with a water depth of about one millimeter (0.04 inch), it signals the driver with a dashboard light and switches to a more sensitive stability-control calibration.
And the stability control becomes even more sensitive if the driver then selects the Wet mode, which has been added to the 992's mode selector. To improve exhaust flow, the stamped-steel manifolds in the 991.2 have been replaced by cast-iron headers. These are said to weigh no more, but flow better, than their double-walled predecessors. The base Carrera will retain the same turbochargers as the 991.2, with a 49-millimeter compressor and a 45-mm turbine wheel. But the Carrera S will get the 55-/48-mm unit used today in the Carrera GTS. The 992 engines also get piezo fuel injectors, which are more expensive than the mechanical direct injectors but provide more precise control of the injection quantity. These changes have allowed an increase in compression ratio from 10.0:1 to 10.5:1, which pays dividends in both power and efficiency. The 992 Carrera S output increases from 420 to 450 horsepower, without any change in today鈥檚 16.0-psi boost pressure. Expect another 30 ponies or so in the new GTS.