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1986 Porsche 944S
A rather obvious price-and-performance gap between the two 944s suggested the need for something in between, and Porsche obliged in late 1986 with the 944S. The attraction here wasn’t a turbocharger but a new twincam head with four valves per cylinder. Though similar to that of the recently introduced 928S4, no parts were shared.
Valvegear was unusual. A single-toothed belt drove the exhaust cam, which in turn drove the intake shaft via a chain between cylinders two and three. Other features included larger-than-944 ports and beautifully cast manifold runners for both intake and exhaust. The result was not only more power and a fatter torque curve compared with the two-valve 944 but smoother power delivery than the Turbo and almost the same punch. The specific outputs: 188 horsepower (SAE net) at 6,000 rpm and 170 pounds/feet of torque peaking at 4,300 rpm.
Model-year ’87 also brought Bosch’s four-channel anti-lock brake system as a 944S and Turbo option, surely one of the most worthwhile contributions to “active safety” ever devised. For passive safety, air bags for both driver and passenger became standard for the Turbo and optional for other 944s in the U.S., making these the first cars available with a passenger air bag at any price. The innovation may seem contrary to high performance, but it only reflected Porsche’s longstanding concern for safety.
More pleasant ’87 developments included higher-tech sound systems and a standard split-fold rear seat to enhance cargo-carrying versatility. A notable suspension change was switching from slightly positive to slightly negative steering “scrub” radius for improved steering control in a front-tire blowout or with one side of the car running on a lower-friction surface.
Conceptually, the 944S was a mix: Turbo-type wheels, normal 944 bodywork and features, in between price. But while twin cams and 16 valves are always neat, the S generated more mixed reactions than even the Turbo. In a September 1987 report, Automobile magazine founder David E. Davis groused that “in the mountains, the 944S wants to be driven between 4000 and 6000 rpm in order to strut its stuff. The 944 Turbo is lazier...In traffic, however, the Turbo becomes finicky -- it won’t be lugged -- and requires just as much shifting as the S.”
But the S avenged itself on the track. “It is forgiving, neutral, pitchable,” said Davis, “maybe the easiest car in the world to drive fast. It scrubs off speed obligingly, using both ends...Any tendency for the tail to come around is mild and controllable... The Turbo, on the other hand... requires both experience and finesse to be driven well at the limit.” Davis put this down to tire differences: 215/60VR15s on the S versus the Turbo’s unequal-size rubber (but an S option). “The two cars, so much alike to the casual onlooker, really define their quite different personas the moment a serious driver sits down behind their respective steering wheels.”
Summing things up, Davis thought the S was the “true next step in the [944’s] evolution... It’s lively, quick [the factory said 7.7 seconds 0-60 mph] and responsive. It has no vices. At $30,850, it is expensive, but we reckon it’s money well spent. The 944 Turbo is lower and meaner-looking...and it transmits an entirely different set of signals to its driver. It feels heavy, but it is also very fast in everyday driving [6.1 seconds 0-60, 10 mph up on top speed at 152 mph]. The combination is an exciting one, but it really isn’t a 944 anymore. It ought to have its own type number.”
Meantime, Zuffenhausen had been wrestling with the perennial problem of how to keep at least one four-cylinder model reasonably affordable in the face of a declining dollar/DMark ratio it could do nothing about. There was also a need to perk up 924 sales in Europe, which had lately fallen off. Again, the answer was about as obvious as the 944 solution.