The real benchmark for the new GT3, however, wasn’t a car made in Modena. Explains Preuninger: “The previous 996 and 997 GT3 models were a huge success. We sold 5,200 cars — more than double the original sales projection, giving us a very strong business case. When we were tasked to make the car even better, we had a lot of sleepless nights as the GT3 had become so good and so well balanced, making it even better was not going to be easy.”
The development path lead the team down several new roads — one of them being new, “smart” engine mounts. In the past, there have been three approaches to motor mounts: soft rubber for mainstream models, firmer rubber for sporting models, and solid (or near solid) for race cars. All of these are compromises along a continuum. Soft rubber isolates engine vibration and road shock-induced movements the best, but it also lets an engine move around as the car takes a corner. In a rear-engined 911, especially, the fact that the engine can move separately creates a separate polar moment of inertia — a destabilizing factor as the engine may still be moving left as you quickly turn to the right. In racing 911s, where the isolation of noise and vibration for driver comfort is not an issue, the engine can be bolted in solidly so that the chassis and powertrain move as one.
Weissach’s solution is Porsche Active Drivetrain Mounts — an option that will be available in late 2009. In recent years, we have seen magneto-rheological damping in the Corvette, Audi TT, and Ferrari 599. PADM uses a similar concept to change the rigidity of the engine mounts. In normal driving, the fluid-filled mounts absorb vibrations and shocks that shift the GT3’s flat six on its mounts. When PADM recognizes more sporting inputs, however, an electrical pulse charges magnetic particles in the fluid, changing its viscosity and, in turn, the rigidity of the mounts. PADM even works as you accelerate from rest, improving traction and reducing the “torque twist” that stresses a drivetrain and obstructs clean gearshifts.
Part of improving any car is listening to your clients, and Porsche took note of buyers who viewed the GT3’s low, plastic front spoiler lip as “sacrificial.” This was especially true in the U.S., where steep driveways and aggressive ramp angles drove GT3 front lip sales to new heights. The team’s solution was a new, optional pneumatic front-end lift system.
Hydraulic lift systems are heavy and slow, some taking up to 20 seconds to raise and lower the front of a car. The Porsche system raises the front end by 1.2 inches in just a second or so and brings the nose back down automatically at 30 mph. The system weighs 11 pounds, sits very low in the car, and locates its pneumatic supply tank near the gearshift mechanism, in the tunnel used by the driveshaft in the all-wheel-drive Turbo and C4S. The pump is the same one used to power the PASM damping system.
If it sounds like Porsche’s purest 911 is getting more and more complex, it is. But Preuninger is quick to point out that his team worked hard to offset any weight gains that came with new technology: “We literally examined every piece of metal and plastic on the car to see where we could remove weight without losing strength.” Thanks to his team’s efforts to trim weight wherever possible, the 2010 GT3 is said to weigh the same 3,075 pounds as the 2008 model, despite all the extra equipment and technical improvements.
The new center-lock alloy wheels are just one example of this philosophy. While Preuninger does not deny the marketing advantages of going to center-locks, he says the 19×8.5- and 19×12-inch alloy wheels are lighter: “There is a 6.6-pound savings across the set of four, 1.1 pounds per rear and 2.2 pounds per front.”
Why do the narrower front wheels save more weight? Specificity — where the last GT3 wheels could be bolted onto a heavier 997 Turbo, the new center-lock wheels are unique to the GT3 and can thus be tailored exactly. With less maximum load capacity, they can be lighter. The system, an evolution of the center-lock hubs used on Carrera GTs and 997 GT3 RSRs, presents two real downsides for trade-up track-day enthusiasts: Their extra five-lug wheels won’t fit and aftermarket wheel choices will be limited, at least initially.