Technology explained Porsche 911 964’s extending rear spoiler

The 964 was the first 911 to utilise an active rear wing, but why is it there and how does it work?

The 964 model, introduced in 1988, may have given the appearance that little had changed over the previous G-series model. In fact that was partly true for the design, which maintained the existing shape and gave it a clean up, smoothing bumpers, and adding an engine undertray. I can recall Porsche Design supremo Anatole Lapine, who oversaw the 964 redesign, joking to me about the impossibility of redesigning the 911 shape, so worked under the car instead; hence the engine undertray.

His jests aside, the 964 was indeed a new model, and claimed to be 85 per cent so over the previous model. Many modern driving aids we take for granted on 911s originated from the 964, which saw power assisted steering, ABS brakes and four-wheel drive feature in a 911. However one debuting 964 feature wasn’t added for technological advancement, but plain old aerodynamics.

In smoothing out the bodywork and adding the undertray, the drag coefficient of the car dropped to 0.32Cd – almost half of the previous 911. Good news, but not in testing, when it was noted the wingless rear of the 964 generated lift at the rear at high speeds. To maintain the clean lines of the then-new car, a neat rear deck lid was created, featuring an integrated, automatically extending rear wing.

With this, at 50mph (80kph), a neat panel incorporated into the rear deck lid rose up, via a cable operated motor, to tame rear lift issues at speed. As the car slowed, and the wing was deemed unnecessary, it then lowered, automatically, at 6mph. Operated via a speed sensor, this meant the clean silhouette of the 964 was maintained until performance dictated extra aero was required. Should the owner wish, a dial on the centre console allowed manual deployment of the wing. It was a typical Porsche solution, to a typically Porsche problem. Porsche Active Aerodynamics (PAA) may just be one more acronym on a spec list today, but don’t dismiss its importance, engineering thoroughness, nor origins. Like so much Porsche technology, the original concept is a historic one, born purely from a need for ultimate sports car performance.