The 928 GTS is Porsche's preeminent Grand Touring model. Since its introduction in March 1977 at the Geneva auto show, the 928 has established benchmarks for all other manufacturers of luxury GTs. At the time of its introduction, the 928, with its all-aluminum engine, extensive use of aluminum alloy in the bodywork, and transaxle layout, set new standards for the state of the art in automotive engineering. Since then, continuous development has kept the 928 at the forefront of technology. Yet time has not changed its character as a high-performance GT of the first order. More than a decade and a half after it changed automotive thinking, the first-class comfort, features and appointments of the 1994 Porsche 928 GTS, coupled with a powerful engine offering remarkable tractability under all speed and load conditions, bear witness to the 928's status in the world of luxury high-performance automobiles.

The 928 GTS with its larger, more powerful engine, was introduced in 1993 as a 1994 model. For 1994, the Porsche 928 GTS is equipped with restyled seats and wheels. Like all 1994 Porsches, the 928 GTS features new exterior color choices.

Engine evolution

Over the years, 928 development has concentrated on engineering. The most signiicant : development changes have affected the engine and suspension. The original 4.5 liter, 219 horsepower engine of 1978 was brought up to 4.7 liters and 234 horsepower in the 928 S of 1983. The original design, with two valves per cylinder, was replaced by a 32-valve double overhead cam engine with 5.0 liters and 288 horsepower in 1985, initially for the American market only, later applied to all 928s. Power was increased yet again for the 316 horsepower 928 S4 of 1987. The 928 Gt of 1989 developed 326 horsepower. Displacement was again increased to 5.4 liters in the 928 GTS of 1993, yielding 345 horsepower.

Unique "Weissach" rear suspension

Porsche's multilink "Weissach" toe-correcting rear suspension, a feature of the 928 from the very beginning, marked a departure in suspension design. The 1984 928 S was the first Porsche to be fitted with anti-lock brakes (ABS), initially as an option. ABS became standard equipment on the 928 S in 1986, and is now standard on all Porsche models. The original one-piston brake calipers of the 928 were replaced by four-piston units in 1986. Porsche's electronically controlled limited slip differential, the PSD, capable of varying lockup between 0 and 100 percent, has been part of every 928 made since the 1990 model year. The PSD increases traction and stability under all driving conditions.

The 928's impact-resistant polyurethane bumpers were redesigned for 1987. The rear spoiler has received continued development since a small lip spoiler was introduced on the 928 S in 1979. The outside mirors were changed for 1993,but the timeless classic shape first seen at Geneva more than sixteen years ago remains.

INTERIOR

Luxury interior

Like the drivetrain and exterior details, interior and comfortfeatures of the 928 line have been continuously improved. The 1994 928 GTS, like its predecessors, emphasizes luxury and convenience in harmony with effortless performance. Many items that were initially available as options have become standard equipment, culminating in today's fully equipped 928 GTS.

The 928 GTS features a fully appointed interior with leather seats front and rear. Electrically- operated front seats, with three memory settings for the driver's seat and outside mirrors, and a fully automatic heating, ventilating and air conditioning system ensure that the occupants of the 928 GTS can travel great distances at high speed, in total comfort, and arrive at their destination relaxed.

The instrument pod, which adjusts vertically in conjunction with the steering column, includes a driver information system capable of monitoring 22 different functions. Warning messages are displayed in three levels of priority. The large, easily read display incorporates trip computer functions.

5.4 LITER ENGINE

Advanced all-aluminum engine develops 345 horsepower

Since its debut at the 1977 Geneva auto show, the all-aluminum powerplant of the Porsche 928 has been one of the most advanced V8 engines in the world. Continued development over the years has increased engine size by 20 percent, to 5.4 liters in the 928 GTS, but power has increased even more, from 219 to the present 345 horsepower at 5700 rpm.

Torque is 369 ft.-lbs. at 4250 rpm. This dry statistic hides the fact that the torque curve of the 5.4 liter engine is remarkably flat; fully 80 percent of peak torque is available in a broad band from 1000 to 6000 rpm. This results in smooth, effortless acceleration even from very low speeds in high gear, conditions that would place undue strain on many competing engines. The low rotational mass of the 928 engine, a characteristic bred by Porsche's racing experience, allows the engine to rev freely and quickly to its 6600 rpm redline, an unusually high limit for a large V8 engine.

The 928 GTS employs a Bosch LH-Jetronic fuel injection system, based on a hot-wire air mass sensor for precise fuel metering combined with low exhaust emissions. The Porsche 928 GTS uses a resonance induction system to improve airflow into the cylinders and thereby ensure improved engine response across a broad range of engine rpm. Dual knock sensors probe the limits of the engine's performance, and permit the fuel injection and ignition systems to dynamically adapt to rapidly changing conditions. A pair of metal substrate three-way catalytic converters with oxygen sensors ensures the cleanest possible exhaust.

TRANSMISSION

Manual or automatic transaxle

The 928 GTS transmits its power through a five-speed manual or four-speed automatic transaxle. The transaxle is located at the rear of the car, instead of immediately behind the engine as is the case with most front-engine, rear-drive cars. The engine and transmission are rigidly connected by a steel tube, which contains and supports the driveshaft. This design ensures uniform weight distribution and improved handling and stability.

Limited slip differential

The transaxle contains not only the transmission, but also Porsche's unique electronically controlled PSD limited slip differential. The PSD uses the wheel sensors of the anti-lock braking system to determine if a rear tire is slipping. Differential lockup is then modulated between zero and 100 percent to reduce wheelspin. The PSD diferential improves vehicle stability under all conditions - hard acceleration, braking, and in curves. This is in contrast to other systems which are not capable of monitoring tire slip under deceleration. Under slippery conditions, traction is improved and the vehicle has a more secure grip on the road Both manual and automatic transmissions employ remote transmission oil coolers to ensure long life.

BRAKE SYSTEMS

Large brakes, ABS standard

In keeping with Porsche's tradition of providing braking performance to match the high levels of acceleration possible with its products, the 928 GTS uses a braking system unmatched by any other GT. The front 12.68 inch (322 mm) and rear 11.77 inch (299 mm) disc brakes each with a four-piston caliper, are taken directly from the 911 Turbo. Like every 1994 Porsche, the 928 GTS has anti-lock brakes as standard equipment.

In brake systems, as in so many other components, Porsche's racing experience has led directly to major improvements for production cars-improvements customers can feel and use every day. Technology transfer from race track to street often results in race-proven systems finding their way directly to the assembly line. For example, the brake system used on the legendary Type 917 race cars in the early 1970s was applied to the 911 Turbo as of 1977.

The key to high-performance braking is heat management. The energy represented by the speed of the car must be converted to heat and transferred to the surrounding air as quickly as possible. Managing this heat transfer requires careful design of the mechanical parts of the brake system, as well as the bodywork and ducting of the car.

Design for optimum cooling

Porsche design parameters for improved brake system performance include the following:

• temperature-resistant engine piston alloys are used for brake caliper pistons
• brake fluid is kept at a lower temperature by the large radiating surtace of calipers
• wear-resistant asbestos-free brake pads provide the highest possible resistance to fading
• use of DOT 4-200 brake fluid, with a higher wetboilling point for greater resistance to fading and extended intervals between brake fluid changes

Porsche's brake discs employ spiral-shaped internal cooling ribs, with additional half-ribs to radiate heat away from the rubbing surfaces. It takes more to duct cooling air to the brakes than simply cutting the biggest possible holes in the bodywork, Too much cooling air low will increase drag and front-end lit Too litle air flow results in overheating and altered brake bias. Porsche has found the best compromise in underbody ducting in the nose, a flexible spoiler attached to the lower suspension arms, and a deflector plate attached to the suspension to direct air through the brake splash shield. Wheel design is also a vital element of the brake cooling system. The openings between the spokes must be designed to extract hot air from under the fenders.

Brake testing in the laboratory and on the road

Porsche conducts extensive laboratory and road tests to optimize brake designs. The final testis how the brake system performs on the road. Porsche tests on famous race tracks such as the Nürburgring and Hockenheimring, and under real-world conditions such as the steep mountain roads on Mont Ventoux in southern France The net result of Porsche's quest for the ultimate in braking performance is that every Porsche production car is capable of extended duty on race tracks without any special modifications to the brake system. In view of such rigorous demands, it comes as no surprise that Porsche brakes provide the utmost in stopping ability under everyday driving conditions.

SUSPENSION AND STEERING

The Porsche 928 GTS continues to use Porsche's innovative "Weissach" rear axle, which was pioneered on the original 928 of 1978. The Weissach axle design employs upper transverse links, lower semi-trailing control arms, and adjustable coil springs over gas pressure shock absorbers. The key to the Weissach axle is a flexible link in each semi- trailing arm, which adds a toe correcting characteristic under high cornering loads. In effect, the Weissach rear axle design offered a form of "four wheel steering"long before the concept gained popularity. The toe correcting feature leads to increased stability at the handling limit and in critical situations, such as when entering turns at unexpectedly excessive speed. An 0.89 inch (22.5 mm) stabilizer bar completes the rear suspension package. The front suspension consists of unequal length aluminum alloy control arms, telescoping shock absorbers, coil springs, and a 1.1 inch (28 mm) hollow stabilizer bar.

Wide 17-inch wheels standard

The 928 GTS is equipped with large 17-inch wheels, with generous air openings to ensure optimum brake cooling. To ensure optimum control while providing the greatest possible comfort, the Porsche 928 GTS employs force-sensitive hydraulically assisted rack and pinion steering.

PERFORMANCE

Zero to 60 mph and top speed

The sophisticated engine technology of the 928 GTS results in sports car performance combined with refined effortless power in everyday driving and relaxed cruising capability. The 928 GTS will accelerate to 60 mph in less than 5.5 seconds with a manual transmission: this luxury GT matches the Carrera 2 and Carrera 4 in acceleration ability. When fitted with an automatic transmission, acceleration to 60 mph takes just a fraction of a second longer, 5.6 seconds. Both versions, with manual or automatic transmission, will achieve a top track speed of 171 mph. (Performance data is provided for comparison purposes only. Porsche recommends obeying all speed laws.)

SAFETY

At Porsche, safety begins with a car's driving characteristics. The dynamic behavior of Porsche sports cars is the result of advanced testing and experimentation, as well as experience on the race track. The results are uncompromising design of suspension, steering, and brakes. Safety considerations are also reflected in the comfort, excellent visibility, and ergonomically correct design of Porsche sports cars.

Highlights of Porsche's safety engineering

Safety is not a new concept at Porsche. As early as 1952, all Porsche cars were fitted with laminated safety glass windshields. In 1956, Porsche offered seat belts as an option on the 356. A 1959 race car, the Type 718, pioneered the articulated steering column which today is used on all Porsche models. In 1961, Porsche offered a shoulder belt as an option, and in the following year made three-point belts available. Racing experience led to the introduction of plastic fuel tanks,first used in the racing-only 911 R of 1967. Plastic tanks are not only impact and fire resistant, but are also impervious to corrosion. Since 1973, every Porsche 911 has been equipped with door reinforcements for increased protection in side impacts. In 1990, Porsche was the first auto manufacturer to equip all of its products with anti-lock brakes. Also in 1990, Porsche was the first manufacturer, domestic or import, to equip every car sold in the United States with driver as well as front passenger airbags as standard equipment.

Structural safety

Airbags and safety belts represent just one level of protection for the occupants, however. The car's structure is also designed for safety, with a rigid cage to surround the occupants and deformable crush zones to absorb impacts. Porsche was the first manufacturer to build car bodies using sheet steel galvanized on both sides. This not only preserves the appearance of the car and the owner's investment, but also maintains the built-in crash- worthiness of the car. Porsche is one of only two manufacturers who feels so strongly about its corrosion protection measures that it provides a full ten-year limited warranty against rust perforation. Even the paint carries a three-year limited warranty.

PORSCHE, SPORTS CARS AND THE ENVIRONMENT

Environmental responsibility

Porsche is not only pioneer in high technology and high performance, but an industry leader in environmental responsibility. This begins with building cars to last. Of all the Porsches built since 1948, it is estimated that 80 percent are still in service. Part of that longevity comes from the fully galvanized bodywork of the Porsche 911. Its durability has been a factor in maintaining Porsche's traditionally high resale values and unparalleled owner loyalty.

Efficient recycling

During development of the 1995 91 1 Carrera, the goal of recyclability of a high proportion of materials used in producing the car was given priority - and achieved. If and when a Porsche reaches the end of its useful life, labeling of various plastic components willmake it easier to reprocess parts, and will help to put plastics back into consumer products, not in landiflls. Lightweight metals, such as aluminum and magnesium, as well as steel, are easily recycled.

Performance withless pollution

Despite their high performance, Porsche cars are among the cleanest on the road. Highly effective three-way catalytic converters, oxygen sensors, and engine management systems have long been partof the Porsche pedigree. Al Porsche models are equipped with systems that fulfill the most stringent exhaust standards worldwide.

Ozone-friendly HFC-134a refrigerant

Growing concern about the possible effects of chlorofluorocarbons, including the CFC-12 refrigerants used in automotive air conditioning systems, on the earth's ozone layer led Porsche to introduce a CFC-free refrigerant, HFC-134a, beginning with its 1993 models. The higher cost of HFC-134a, and its higher salvage value, also provide a monetary recycling incentive for repair shops.

SPECIAL OPTIONS AND EUROPEAN DELIVERY

Special-order options available for all Porsches

Porsche owners who would like to further personalize their cars can take advantage of Porsche's special options program. Porsche offers a wide range of special order items to make each car uniquely individual. These include paint to match any sample color and leather to dupli licate any sample shade. Virtually every interior item may be ordered with factory-applied leather trim.

Porsches European delivery

Every Porsche may be ordered through participating U.S.dealers for European delivery This program offers an unforgettable driving experience, enabling the buyer to sample the high-speed motorways and scenic, winding secondary roads which gave birth to the Porsche legend.

WARRANTY

Broad warranty coverage

Thanks to decades of experience building solid, urable high-performance cars, Porsche's warranty coverage is among the broadest of any sports car manufacturer. Each Porsche is covered by a two-year new vehicle limited warranty with unlimited mileage, which includes the Porsche roadside assistance program. The fully galvanized body and 26-step paint and anti-corrosion process enable Porsche to warrant each car for ten years and unlimited mileage against rust perforation, protection unmatched by any other sports car manufacturer. In addition, the paintwork carries a three-year limited warranty.

Two-year parts warranty

In addition to the extensive warranty coverage of Porsche cars, Porsche also warrants parts and accessories for two years and unlimited mileage. For parts and accessories installed by authorized Porsche dealers, labor costs are also covered.

LEASING AND FINANCING

Porsche Credit Corporation offers attractive leasing, financing and balloon payment plans for new and used Porsche sports cars. The "Porsche Preferred Lease" program is available for new Porsche sports cars and for 1991-1994 pre-owned cars. The lease term can be as long as 60 months. Finance terms of up to 84 months are available. The "Porsche Options" program combines the economies of leasing with the benefits of ownership for new Porsches as well as 1990-1994 pre-owned Porsches. (Certain programs may not be available in all 50 states.)

Attractive leasing terms for new and pre-owned Porsches

These financial options allow more American drivers to enjoy the thrill of the Porsche experience, an experience which draws on Porsche's legendary heritage as the maker of both the world's finest performance automobiles and some of the most innovative and successful cars in the history of automobile racing.