The new Porsche 911 Carrera 4 provides excellent all-weather traction with standard permanent four-wheel-drive, traction control, ABS, and a new anti-skid system called Porsche Stability Management.
The perfect all-weather sports car
Recently, I had the opportunity to test-drive the 1999 Porsche 911 Carrera 4 at Road Atlanta racetrack in Georgia, not far from Porsche North America’s new headquarters in Atlanta. Here, I was able to take the car to its limits on the racetrack, on a circular skidpad that had been ‘wetted down’ to simulate rain-slick roads, through a slalom and lane-changing simulation, and on a short handling circuit. In addition, I was able to drive on backroads through the North Georgia mountains, a scenic and little-known driving route that includes mountain switchbacks, ambling two-lane country roads, and picturesque little towns.
The purpose of driving the Carrera 4 at its limits was not just a thrill-seeking exercise (although, believe me, it was a thrill). The purpose was to test the new Carrera 4’s revised all-wheel-drive system and new anti-skid system in a safe and controlled environment.
In a reversal of safe driving practices, Porsche representatives asked me to deliberately lose control of the car, and allow its active safety systems to restore directional stability and traction. Doing this required some faith in Porsche’s engineers and technicians. The 911 Carrera 4, based on the recently redesigned 911 Carrera 2, already has such high cornering limits that losing control requires considerable recklessness – in fact, you have to be a really bad, or unlucky driver, to lose control of a 911 Carrera 4 – at least on dry surfaces.
And that’s really the point of owning a 911 Carrera 4 vs a Carrera 2 – the Carrera 4 is an ideal sports car for driving in bad weather, perhaps the perfect car to drive on a twisty highway on a wet or icy winter night.
The secret to its tenacious traction is a combination of all-wheel-drive, a rear-biased weight distribution (for better traction), a low center of gravity, independent suspension, anti-lock brakes, traction control, electronic brake differential, superb Pirelli high-performance tires, and the coup de gras, a new anti-skid system called Porsche Stability Management or ‘PSM’.
Using computers and numerous ‘g’ sensors and ‘yaw’ sensors, PSM combines ABS and traction control with lateral stability controls to restore directional control when the car begins to spin or slide. Specifically, if a driver goes too fast into a corner and begins to understeer (ploughing into the corner), PSM momentarily brakes the inner rear wheel to bring the car around to the proper direction. If a driver experiences oversteer in a corner (rear-end swings out), PSM automatically brakes the outer front wheel causing the car to regain control and direction.
Though Porsche is not the first manufacturer to use this technology (Mercedes-Benz, BMW and Lexus have similar systems), the Porsche system has a higher activation threshold and interferes less with the driver’s control. PSM can be switched off via a button on the dashboard, but in my test-drive, I didn’t find this necessary. By the time PSM activates, you’ve already lost control, and the joy of driving has turned to terror.
Even with PSM turned off, a touch of the brake pedal activates it, causing the car to regain control. Of course, the Porsche 911 Carrera 4 cannot defy the laws of physics, and there is a point when even PSM cannot restore stability (say for example, when you leave the ground…)
The Carrera 4’s all-wheel-drive system has a viscous clutch between the front and rear axles which has been moved from the gearbox to the front differential housing for better weight distribution. In normal driving conditions, 95% of the engine’s power goes to the rear wheels and 5% to the front, but up to 40% of the engine’s power can be directed to the front wheels.
Abundant power and torque is supplied by a 296 horsepower 3.4 liter water-cooled horizontally-opposed six cylinder engine mated to a standard 6 speed manual or optional 5 speed Tiptronic transmission. This is the first time the Tiptronic transmission has been available with all-wheel-drive, technology made possible by a new electronic throttle and gas pedal.
Available as a coupe or convertible, the 911 Carrera 4 ranges in price from $103,200 to $121,830. Understandably, the Carrera 4 will appeal mostly to driving enthusiasts with a lot of cash or a very friendly bank manager.
Overall, I’d say this is the finest, all-weather sports car now available, and will handle any inclement weather condition except deep snow (there’s not enough ground clearance). I guess that’s where Porsche’s future sport-utility vehicle will take up the mantle.