Designed in 1971 as the eventual replacement for the 911, production of the 928 was delayed until late 1977 as a 1978 model largely due to the coming fuel crisis. As such, it lays claim to the title of first front-engine, water-cooled Porsche despite the 924's introduction two years before that of the 928. As prices inflated in the late '80s and into the '90s, sales of the big Porsche fell off leading to its eventual cancellation in 1995. Only a few hundred GTSs were ever sold in North America.
|Electronic fuel injection debuts in 1980.
|928 S becomes available in Europe only with a 300 hp 4.7l engine. U.S. receives Competition Package in 1981 w/ S spoilers but not the motor.
|New DOHC U.S. motor with 4 valves per cylinder. Euro S continues with 310 hp SOHC 4.7l motor.
|First of the new body style. "S4 brakes": 11.97" brake rotors w/ 4-piston calipers introduced on late '86 models. Difficult to adjust dual-disc clutch replaced with single disc unit.
|Computer-controlled limited slip differential derived from technology pioneered on the 959. 5-speed only. Tightest 928 suspension.
|1992 only available in Europe after mid-year. "GTS brakes": 12.68" rotors with still larger 4-piston calipers.
Over its entire production span, the 928 went through one significant body change. In 1987, the fourth generation S4 shape was smoothed out for better aerodynamics, given flush tail lights, and a new wing. Only the nose and tailcap changed. The mechanicals were periodically upgraded, but the layout and all features remained basically the same. The 5.4 liter GTS even shares the same block with the first 4.5 liter 928 and still had another 0.6 liters of stroke to go in its design. A GTS owner would feel very at home in the first '78 to roll out of the factory. That says a lot for a design now almost 30 years old.
Strictly speaking, the 928 is more grand touring than sports car. It is fully laden with all the best luxury features and a big, powerful motor. The S4 is equipped with Porsche's 5.0 liter (303 cid) DOHC, 32-valve all-aluminum V-8 motor. It was built to fly down the autobahn in excess of 140 mph for hours on end without tiring the driver, but is equally at home on twisty back roads.
Porsche pioneered many technical features on their flagship luxury coupe including the famed Weissach Axle which was later adapted for use on other models. It is an automatic toe-correcting system which can be thought of as a sort of passive rear-wheel steering — the first of its kind available to the public. It helps keep the rear wheels on track in certain lift-throttle or braking situations lending a very neutral, easy handling — a significant change from the tail-happy 911s in '78.
Another innovation was the aluminum/silicon engine block designed without the mechanical protection of steel cylinder sleeves. Instead, the bores were etched to expose the silicon crystals providing a very hard, durable wear surface. In fact, aluminum was used quite extensively throughout the 928 including just about everything in front of the A-pillars and most other major castings. This lent considerable weight savings, a necessary component given all the luxury packed on the car.
My car came with the rare 5-speed transaxle. It is interesting to note that the gearbox is mounted in back, something the C5 Corvette borrowed from Porsche 20 years after the first production 928 and 22 years after the first 924. This was done to achieve a near 50-50 weight distribution.