Evolution of the 911

By Dean Lewellen
reprinted from Going Places, official newsletter of the Arizona Region PCA

The Porsche 911 body shape is the visual icon of the sports car that has become permanently etched in our minds since its debut in September 1963 at the 41st International Automobile Show in Frankfurt am Main, Germany.  Forty years of continuous product development and engineering refinement of the original configuration, defined in late 1961, have made the 911 immortal in the automobile world.  This article covers the chronology of the car’s evolution and gives some details about individual models/series introduced along the way.  The references at the end of the article would provide the reader with much more specific and exacting detail on the 911’s history than can be condensed into this space.  All are excellent sources and great reads as well.

At the Frankfurt auto show, Porsche designated the new car as the Model 901.  The development of the Model 901 continued until the car was shown again in October 1964 at the Paris Auto Salon where Porsche announced that deliveries of the first production cars were imminent.  This got the attention of Peugeot, who, since 1929 had been giving its automobiles three digit designations with a zero in the middle and had an exclusive French trademark registered.  Peugeot complained, and, as a quick, backroom solution, Porsche changed the middle digit from a “0” to a “1”, and thus, the Porsche Model 911 was born.  The rest of the story is history.

Before production started in November 1964, a total of thirteen 911 prototypes were built for display, testing and development.  No two examples were alike.  They underwent continuous modification and differed from the production cars in many details.  Commonality that exists with today’s Model 996 is that they had a horizontally opposed six-cylinder engine mounted aft of the rear wheels, a 2+2 seating arrangement, and, a side profile that is unmistakable down to the rear quarter windows.

Model year 1966 marked the introduction of the Model 912 which utilized the four-cylinder engine of the Model 356SC. (Sue Herrman has an immaculate one-family owned example of this car).

1967 marked the introduction of Butzi Porsche’s “Targa” open-air model, which is an identifiable worldwide trademark Porsche name and was intended to recall Porsche racing successes in Sicily in the “Targa Florio” road race.  An increase in engine power to 160 HP marked the introduction of the first “S” model in the lineup.  The forged “Fuchs” aluminum alloy wheels were introduced in a width of 4 1/2 inches for the 911S.

The first emission rules of the United States became effective in 1968, which meant we didn’t get a 911S with 160 HP, but instead, got a 911L with the 130 HP engine from earlier years.  This was the first year of several to follow where the differences between Porsches exported to the USA and those sent to the rest of the world was dramatic.  The “Sportomatic” semi-automatic transmission was introduced along with the 911T (Touring), which was powered by a reduced output 110 HP engine.  (ugh)!

1969 (B-Series) was a significant year for the 911.  There were extensive body changes: longer wheelbase (2 inches), altered fenders and revised lighting.  Also new were fuel injected engines to cope with US emission rules for the new Model 911E and reintroduced 911S.  The S engine now produced 170 HP.   The E and S engines were equipped with Bosch mechanical fuel injection systems.  Other features such as twin batteries (one in each forward wheel well), a real glass rear window in the Targa, and 6-inch wide Fuchs wheels on the 911S were part of the lineup.

1970 (C-Series) marked the end of the Model 912 and an increase in the 911’s engine displacement to 2195 cc’s (2.2 liters).  911S power was now 180 HP.  The Model 914 was introduced to provide an entry level Porsche, but that’s another story.

The 911 was changed very little in 1971, and, in 1972, the displacement was increased to 2.4 liters producing 190 HP in the 911S.  The shift pattern for the transmission was changed to what we are familiar with today with first gear forward and to the left instead of back and to the left.  This new transmission was known as the type 915 and was designed to handle the power increases current and planned.

The 1973 911 (F-Series) marked aerodynamic improvements in a way of an air dam on the 911, and, the “duck tail” spoiler on the newly introduced 911 Carrera RS.  The 911T received the K-Jetronic fuel injection system in mid-year.  With the US Government imposed rules against tetraethyl lead as an anti-knock additive for gasoline, the 2.4-liter engines of 1972 and 1973 were designed to run on regular grade fuels.

 1974 (G-Series) was a year of extensive body changes, which were required to meet US bumper regulations for impact resistance and height from the ground.  Gone from the lineup was the 911T and the K-Jetronic injection system was fitted to all engines, which saw another displacement increase to 2.7 liters.  A single battery replaced the dual batteries in the front trunk.  A “Plain Jane” 911 with a 150 HP engine and a 911S with a 175 HP engine completed US choices.  The 911 Carrera model with a 210 HP mechanical fuel-injected engine was available overseas.  A Carrera trim 911 with the 175 HP engine was available in the US in small numbers.

 1975-1976-1977 model years (H, J, K-Series) can be grouped together and represent the darker years for Porsche in the US with a few exceptions.  The ever demanding emission rules by the US and by then California’s unique requirements took its toll on the drivability, survivability and performance of the K-Jetronic injected engine.  Power output of the 2.7-liter engine dropped to 157 HP for all states and 152 HP for Porsches delivered in California.  Piled onto the engines were an air pump to dilute exhaust gas emissions and thermal reactors (read early catalytic converters) to burn excess oxygen in the exhaust.  What really happened was that the reactors cooked the sealant in the block seam and block/cylinder/head joints.  You can imagine the rest.<

 A Model 912E was introduced in 1976 for a single year to bridge the gap prior to the introduction of the Model 924 in 1977 and provide a means to use up left over 914-2.0 engines.  A Carrera trim 911 with the 157/152 HP engines was available in small numbers (395) in the US in 1975 as well.

 A bright note for this period was the introduction of the Model 911 Turbo Carrera in 1975 in Europe and in 1976 in the US.  This car was powered by a 3.0-liter engine equipped with an exhaust driven turbocharger that produced 260 HP!  This Porsche had a top speed in excess of 155 mph and would provide a rush for the occupants in achieving 60 mph in less than 5.5 seconds.

 The 1978 Porsche 911SC (L-Series) marked the emergence from the dark years of the mid-seventies.  Engine displacement was increased to 3.0 liters producing 180 HP, while the Model 930 Turbo produced 265 HP in the US and 300 HP for the rest of the world (RoW).  The SC’s were/are great looking Porsches with flared rear fenders of the European and US Carreras, optional air dams and rear spoilers, comfortable interiors with air conditioning, leather and with great drivability and handling characteristics.  The 930 Turbo was billed as the fastest production automobile on the planet with a top speed of 260 km /h (156 mph).

 1979 and 1980 saw no changes for the 911SC except for the awful speedometers that were specified to meet US rules and showed 80 mph as the largest number on the dial.  US imports of the 930 Turbo stopped at the end of the 1979 model year as the three-way catalytic converters and the turbo waste gate integration needed more development.

 The 1981 through 1983 model years saw a power increase of the 3.0 liter 911SC engine to 204 HP and a rust perforation warranty of seven years on the body, which was a first in the industry.  Other improvements included the departure from the troublesome rubber-centered clutch disc, plusher interior appointments and the return of a Cabriolet model in 1983 after an eighteen-year hiatus.  The 1983 911SC has the reputation of being one of the most bullet proof Porsches ever built.

 The 1984 Carrera (E Program) was the leadoff model year for the series of Model 911 Carreras produced through the 1989 model run.  These cars are very similar in their basic specifications with 3.2-liter engines, Digital Motor Electronics (DME), solid driving and handling characteristics and great creature comforts.  They are often referred to as the last of the “Real 911’s”.  The engine produced 207 HP in the 1984 car and was increased to 217 HP in 1987.  Six and eight inch wide or seven and eight inch wide wheels were fitted depending upon model year and driver preference.  A change to a hydraulic actuated clutch was made in 1987 together with the introduction of the G 50 manual transmission.   The 911 Turbo was reintroduced to the US market in 1986 available as a Coupe, Targa or Cabriolet model.  Turbo power was rated at 282 HP./p>

 In January of 1989, production began in a new body factory of the new Model 964, AWD Carrera 4 (K Program).  This car was 70 per cent new, utilized the AWD technology of the Model 959 and Paris/Dakar Rally cars and was powered by a 3.6-liter, twin spark plug engine producing 250 HP.  The remaining 911 bodies left in the old body factory were used to produce the 1989 Speedsters, which are coveted today in some circles.

 The 1990 through 1994 Carrera 2’s and 4’s shared most components except the AWD machinery and computerized controls.  These cars, including the engines were truly, one-world automobiles, as the requirements of the rest of the world, the European Common Market emergence, and the US rules reaching a plateau had given most manufacturers a clear set of requirements to strive for in their designs.  A one-world Turbo coupe was offered in 1991, still using the3.3-liter engine rated now at 320 HP.  The Turbo’s engine was enlarged to 3.6 liters in 1993.  Another “common” was that all Porsche engines were designed to operate on unleaded fuels, which reduced combustion deposits and extended spark plug life.  The 4-speed Tiptronic automatic transmission was introduced as an option on the 1990 Carrera 2.  The Carrera 2 and 4 coupes and Targas ceased production in July 1993.  The Cabriolet and a few Speedsters continued until January 1994, as did the Turbo 3.6.

The Porsche Model 993, advertised as “The New 911” in its early days, began first deliveries in the US in the Spring of 1994 as a 1995 model.  The car was an overnight success with waiting lists forming at many dealers.  It was sensuous and sexy when compared to the smooth but drab Carrera 2/4 predecessors.  Interestingly, the 993 used the same 3.6-liter engine rated at 270 HP for 1995 and then revised to 282 HP for 1996 and beyond by the variable length intake runner system.  A G 50 six-speed, manual transmission or the Tiptronic automatic transmission was available.  The systems on the 993 are modern with power steering (first on a 911), climate control air conditioning/heating, power ABS brakes and traction control with ABD.  These cars are now known as the “last of the air-cooled” Porsches.  A twin-turbocharged 993 Model was introduced in 1996, reclaiming the title, “fastest production car on the planet.”

 The latest step along the evolutionary path is the Porsche Model 996.  As the car evolved, the latest step seems to be the greatest departure from the past.  The 996 arrived in May of 1998 and left all air-cooled fanatics in the used car-shopping mode.  The 3.4-liter engine is water-cooled, semi-dry sump lubricated, and the car is larger in length and width.  The water-cooling allows room to incorporate a four-valve per cylinder head design and aids in overall engine noise reduction as well.  Gone are the five individual gauges on the dashboard, the mechanical whine of the chains and cooling fan, the shoulder-to-shoulder intimacy of driver and passenger.  It is difficult to detect the lineage with the past from inside the 996, but when you stand alongside, you can feel the visual and emotional connection to its heritage.

Aichele, Tobias, Porsche 911 Forever Young, 1995

Haab, Mark S., The 1974-1989 911 Porsche, Authenticity Series, 1995

Ludvigsen, Karl, Porsche Excellence Was Expected,  1977