Speed freak

IT’S taken me this long to recognize what I love about a Porsche 911 Turbo. And no, it’s not the internal-combustion volcanism — now up to 480 hp in the 2007 model — or the claws-in-the-carpet grip, the carbide-steel stiffness, the perfect steering or land-anchor ceramic brakes.

It’s this: The 911 Turbo is the only ultra-performance sports car that’s in good taste.

I direct you to Road & Track’s cover story this month, a six-way runoff among the Porsche, the Dodge Viper, Chevrolet Corvette Z06, Ferrari F430, Ford GT and Lamborghini Gallardo. The editors have spared no trouble metering and measuring the performance of these cars, with the result that they are all within tenths and milliseconds of one another. You might as well draw names out of a helmet. Each of these monster cars will wring your adrenal glands like a pair of wet socks; each would qualify as karmic reward for a life spent working for world peace or curing halitosis or something.

Now imagine yourself driving them — which is to say, see yourself as others would see you on a day-to-day basis. Ah, well, now these cars become a decidedly more mixed proposition. Face it, with the exception of the Porsche, these cars do not cover their owners with glory. They are too vulgar, too boorish, too, too much. The Corvette is the subtlest of the bunch, and the Vette is about as subtle as a smoking exit wound.

Taken together they constitute a gallery of male midlife symptoms so classic as to have their own pages in psychology textbooks. You know it. I know it. The woman next to you at the light waggling her pinkie finger at you knows it.

Now we come to the Porsche 911 Turbo. This is the sixth generation of flagship Turbo, and though there are lots of visual cues of its lycanthropic Turbo-ness, it looks pretty much like a standard-issue 911. Only other car enthusiasts — and 8-year-old boys — will discern the difference: the ventilating strakes in the front and rear bumpers, the filament-like turn indicators (LEDs), the dual engine intakes on widened hips, the active split-wing spoiler, the heroic 19-inch wheel-and-tire package.

In other words, the Turbo enjoys the understated dignity that attends the regular 911 while delivering performance comparable to the latest Lamborghini crotch-stuffer.

Look, I’m not saying the Gallardo doesn’t have its uses. If I were a teenage millionaire and I needed a smooth surface from which to blow rails, the Gallardo’s hood is first choice. Meanwhile, my vote for the world’s sexiest car? A 911 Turbo, slightly lifted, with extreme snow tires and a ski rack on top, covered with road salt and grime, bashing up the road to Whistler in British Columbia. I think I might even kick a dent in one of the new all-aluminum, 22-pound doors. That’s filthy hot.

The big news with the 911 Turbo is that Porsche has essentially banished the torque curve with its new variable turbine geometry. While you nod solemnly, I’ll explain. Internal combustion engines can be thought of as air pumps, which have a peak efficiency — volumetric efficiency — at a certain rpm depending on the character of the engine. European-style overhead cam engines work better at higher rpm; big thrusty pushrod V8s are more efficient at lower rpm.

All this is true if the internal components of the engine — induction and exhaust, valves, cams, crankshaft, pistons — are in a fixed relationship to one another. The advantage of variable-geometry induction and variable-valve timing is that they broaden the range of rpm at which the engine is efficient.

Conventional turbochargers — devices that use exhaust gas energy to pressurize air being fed to the engine — increase airflow but are themselves restricted by their size. A small turbocharger spins up fast but doesn’t deliver a lot of boost; a big honking turbo crams a lot of air down the engine cakehole but requires precious milliseconds to spool up, causing “turbo lag,� which affects drivability. You put your foot down, count one … two … threeee!!!

The Porsche’s new water-cooled turbos have turbine vanes with variable pitch so that the effective cross-section of the turbo changes depending on engine speed and load. Variable-pitch turbines have been used in turbo-diesel engines for years, but the higher temperatures of a gas engine made them difficult to engineer for sports cars.

Combined with Porsche’s revised variable-valve timing (VarioCam) — and a host of exotic engine upgrades and cybernetic engine systems such to make your local ASE-certified mechanic want to hang himself from his lift — the flat six now produces 480 hp out of a mere 3.6 liters of displacement, or 133 hp per liter. More important for purposes of blowing your mind, the engine generates 460 pound-feet of torque between 1,950 and 5,000 rpm. Forget peak torque. Welcome to Torque Plateau, or Torque Mesa, or the Bonneville Torque Flats.

Meanwhile, cars that are equipped with the optional Sport Chrono package — as our test car was — have the automotive equivalent of “Star Trek� auxiliary power. With the Sport function engaged, turbo pressure increases to a maximum of 17.4 psi (1.2 bar) for a 10-second overboost of 505 pound-feet between 2,100 and 4,000 rpm.

Gee, that’s a lot of numbers, isn’t it? What’s it all mean? It means that when you squeeze the accelerator and drop the clutch — wham! — your brain sloshes against the back of your skull and your tongue wants to hide between your tonsils. Holy hell! Zero-to-30 mph goes by in about one second as all that torque instantly sets all four Z-rated tires to churning. It’s like getting swatted in the back by Grendel in the mead hall. Think fast. The rev limiter comes on at 6,750 rpm — too late! Next on the agenda: second gear.

With practice, you can launch the car at about 3,500 rpm and anticipate the first-second shift, so that you can reach 60 mph in about 3.7 seconds. It is not easy, but it is all grades of fun. The soundtrack to all this is a ferocious chirr of very expensive parts gnashing together and a fearsome whoosh of induction noise as if you were being sucked face-first into a Harrier jet engine. Keep your foot down, execute one more shift and you will reach 100 mph in 8.4 seconds. Beyond that you’ll enter a weird dissociative state in which you lose the power of speech and other vital bodily functions. Man, is this car fast.

But it’s not just fast. It’s potent, constantly energized, strung like a catapult waiting to let fly. Even in fifth gear, acceleration from 50 to 70 mph takes 3.5 seconds with the Sport mode on. Any gear, torque is here. All this puts the Turbo on another plane of performance from surrounding traffic. Indeed, other cars move out of the way as if paralyzed by some reef-fish neurotoxin.

With the addition of this extra stomp, Porsche was obliged to upgrade the rest of the powertrain. The six-speed gearbox has been reinforced, and the gear ratios have been altered to account for the new 19-inch wheels and tires.

Meanwhile, the viscous-coupling diff of the all-wheel drive system has been replaced with a stouter multi-plate clutch system. If the wheel sensors detect loss of traction at the front or rear axles, the diff’s electromechanical actuators can react within 100 milliseconds. This is only the first layer of the Porsche’s vastly complicated process for keeping the car’s sunny-side up, including active damper system, the speed-sensitive rear wing (the car generates significant downforce at speed, while maintaining an aero-oily 0.31 coefficient of drag); and the stability management system.

The stability system has a cute trick: If the driver lifts off the pedal quickly, it will feather the brake calipers, quickening brake response, which could help in saving the car from a noisy finale. Also, six-speed models have the option of a locking rear diff, for better power-on cornering.

All this plays symphonically well together, so that from the driver’s seat all you feel is fluidly precise handling that makes you feel like a genius behind the wheel. Beyond that, the singular sensation of the 911 is one of case hardened steeliness. Superman couldn’t bend this car.

The other remarkable thing about the Turbo is that it’s faster with an automatic transmission than with the six-speed manual. Thanks to a highly massaged interplay of the Tiptronic S transmission, the engine and the all-wheel-drive’s traction-management system, the auto-equipped cars are a full three-tenths faster to 60 mph (3.4 seconds). Help me out, car-noscenti: Is this the quickest automatic-equipped production car ever? I believe so.

I can’t tell you much about that, because I didn’t drive a Tiptronic S version. I guess this means I’ll have to test another 911 Turbo in the near future.

The things I do for you people.

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2007 Porsche 911 Turbo

Base price: $122,900

Price, as tested: $141,445

Powertrain: Rear-mounted, turbocharged and intercooled, 3.6-liter horizontally opposed six-cylinder, 24-valve, dual-overhead cams with variable valve timing and lift; six-speed manual transmission; all-wheel drive.

Horsepower: 480 at 6,000 rpm

Torque: 460 pound-feet at 2,100-4,000 rpm; with Sport Chrono function, 505 pound-feet at 2,100-4,000 rpm

Curb weight: 3,495 pounds

0-60 mph: 3.7 seconds

Wheelbase: 92.5 inches

Overall length: 175.2 inches

EPA fuel economy: 19 miles per gallon city, 25 mpg highway

Final thoughts: Aristocratic assassin