Porsche’s newest track-ready 911 GT3 arrives with a few new and unexpected pieces of technology. For one, it’s the first GT3 with stability control. And it’s the first Porsche armed with dynamic drivetrain mounts.
During hard cornering, even the tiny shifting movements of the powertrain—which accounts for about 20 percent of the GT3’s weight—can upset handling dynamics and corrupt steering accuracy. The mounts hold the powertrain tightly during frenzied driving but relax their hold during easy going. If the mounts were stiff all the time, the noise and vibration transmitted from the engine to the body would produce driver comfort on par with that of a World War II VW Kübelwagen.
The GT3’s engine mounts work through the magic of magnetorheological fluid (the same stuff found in some variable shocks). An electromagnet in the mount produces a magnetic field, which causes the fluid to alter its viscosity immediately. Change the voltage applied to the electromagnet, and you can instantly make the fluid thinner or thicker. The engine-management computer regulates this voltage according to a map based primarily on engine rpm.
Source: Car and Driver