The Engine—And How It Sounds While the 991 GT3 shares a few parts with the current Carrera—such as crank case, timing chain, and alternator—this is almost an entirely new engine. Don't let the six-cylinder's 3.8-liter displacement fool you. Everything about the character of this engine is different vs. the prior GT3. The makeover wasn't just about increasing redline (from 8400 to 9000 rpm), but also producing power at a higher rev range. That, in conjunction with tighter gearbox ratios—and all in concert with a freer revving engine—results in a motor that races toward seven grand the instant you punch the accelerator. That's the goal. To keep everything simmering just below boiling. So while peak torque of 324 lb-ft arrives at 6250 rpm, the 475 horses aren't extracted until a roaring 8250, and it's the getting there that counts. Part of that was simply shedding weight; the new engine is about 55 pounds lighter than the outgoing 435-hp GT3, with a catalogue of parts changes including a lighter oil pan separator, a carbon composite intake, and lighter headers. Few motorcycles feel this free to rev. But the flip side is that this motor wants to rev. At idle it's gruff and a little cranky, like a bulldog straining at its leash. Past 911 motors have sounded cleaner, more placid in traffic. But this engine wasn't built for traffic. Bang into the gas, let the beast roar, and its true demeanor cooks through to the surface. If you're a bystander as the GT3 goes by at full tilt, you feel it in your bones. Feet vibrate on the sidewalk. Heads turn to see what's coming as the throaty rasp clangs off concrete buildings. Children stand by, gobsmacked. Their parents stare, slackjawed. But...is the sound pretty? No. Ferraris sound pretty. The GT3 sounds menacing and awesome. Lovelier music has been made from six-cylinders, but when you're at 4000 rpm and in a hurry, a quick tap-tap of the left paddle of the GT3's PDK gearbox will get you all the respect you need. The GT3 grows more civilized with an auto mode, ideal for when you're stuck in traffic, but there's also a PDK Sport mode, which was uniquely designed for optimal down- and upshifts on the track. Gears are held right to redline, and upshifts are only executed when you've passed the horsepower peak. Is Rear-Wheel Steering a Gimmick? After a few hours in the GT3, including more than one U-turn to get un-lost, and dozens of rocket blasts down contorted intersections of country lanes mashing directly into highways, it's easy to laud the attributes of four-wheel steering. Very simply, it has the effect of making the car feel shorter at slow speeds, turning the rears away from the direction of the fronts below 31 mph, so slow-speed radiuses get tighter. Above 50 mph, the rears turn in concert with the fronts, virtually extending the length of the GT3 by a massive 20 inches. That high-speed flight I executed in the pouring rain no doubt felt more stable because the rear of the car seemed to grow aft. There's surely a limit to how much stability can be gained, but one effect you feel is well-weighted but seemingly lighter steering at higher speeds. The car executes lane changes precisely and sharply, but without any dartiness. Bigger, Badder The 2014 Porsche 911 GT3 is 1.7 inches wider than a 911 Carrera S in the rear, and the wheelbase has grown 4.7 inches since the gen-four model. While the body is based on the current 991 Carrera S, aluminum panels (roof, doors, engine lid, fenders) make the entire shell 13 percent lighter than the outgoing GT3, even while torsional rigidity shoots up 25 percent. The car also sits about an inch and a half lower. In the U.S., there's an optional suspension-lifting switch to help avoid scraping the front apron on the deep curb cuts common to American driveways. In case you missed it, there's a fixed, massive tail on the rear deck. Functionally, Porsche says the lengthened lip helps increase downforce at the rear axle. The design is a combination of composite, fiberglass, and carbon fiber. The front apron is also new. Larger vents increase air supply to the radiator, a wide spoiler lip increases downforce, and intakes funnel air beneath the car to provide additional downforce via diffusers, to prevent lift in the underbody where the undercarriage naturally lifts at the rear-mounted engine. Suspension - More Compliant, And Also More Stable If you just climb aboard the GT3 and drive off without fiddling with the suspension settings, you'll be treated to a surprisingly civilized ride. Yes, it sits lower, but suspension travel is increased, and the dampers default to a reasonable level of cushioning that's apt for even race-car speeds. Most of my testing was done in this mode, and even Porsche's own 7:25 lap time on the Nürburgring Nordschleife was achieved in this mode, because that's a notoriously bumpy track. But if you intend to race (Porsche says 80 percent of its GT3 customers track their cars) there's a more aggressive Sport mode. Even so, it's not excessively brutal for well-paved roads. The adaptive suspension system wrings out more violent gyrations before they overly disturb the chassis. Putting the Power Down Porsche says the PDK was needed in part to be able to implement Torque Vectoring Plus (PTV Plus). This integrates a variable locking diff, as well as rear-wheel braking. In essence it's a constant balance of applying horsepower and selectively shortening turning circles. So in addition to rear-wheel steering, once you turn the steering wheel the inside rear wheel slows down slightly, effectively overdriving the outside rear wheel and pitching you more cleanly toward the intended apex. Simultaneously, when exiting a turn the active differential can act on a continuum, rather than entirely locking up, sending us much available power to the ground based on grip, but preventing total mayhem. More succinctly, it makes you go faster. Interior—Almost All Business You won't ever confuse the GT3's interior for that of a Ferrari 458, but it's gorgeous if you believe in what Porsche stands for. The suede-wrapped steering wheel is perfectly shaped with "thumb-lock" slots above the T-shaped hub, the seating surfaces are grippy in suede, and door grab handles are likewise double-stitched in the same material. Aluminum accents grace the dash, and mildly highlight interior shapes. And you can go after even more of a track look with rear cross bracing (there's no back seat regardless) and full race seats, complete with six-point harnesses. Right now, you cannot order the car with sport bucket seats because they don't meet U.S. side airbag standards. You may not miss them. They only feature fore-aft rake, and there's no tilt. While excellent for aggressive driving, in traffic you might want more lumbar support or the ability to adjust height (shorter or taller drivers will need more adjustment for certain). Functionally, even if there's less panache to this cabin than you'll find at the supercar level (don't forget that at $131,000 this car is technically fighting leagues above its class), it all works. Often the flashier cabins at double or triple this price look stupendous (like the sunken living room of a show home), but they aren't all that functional. The GT3 absolutely works.