The 911 is a rear wheel drive, rear engined automobile. Rear engined meaning the engine is behind the rear axle. Its engine is a horizontally opposed 6 cylinder. Horizontally opposed pistons lay "flat", hence the name "flat-6." The first actual 911 models are considered 1965. In 1965 and 1966, the 911 came in only one form. It had a 1991cc engine, which produced 130 horsepower at 6,100 rpm. They used Solex carburetors, and had a compression ratio of 9.0:1. This car's top speed was about 130 mph.
the 911 model remained unchanged, but was joined by the 911 S. By 1968,
more options were added to the Porsche--like a sunroof and the Sportomatic
gearbox. This gearbox was like a normal 4 speed transmission, except there
was no clutch pedal. The clutch was controlled by two microswitches at
the base of the shifter. All the driver had to do was touch the shift
knob, and the transmission would go into neutral, awaiting the next gear
to be selected
The 911S (Super) appeared in the model lineup in 1967. The 911S had the same engine displacement as the regular 911, except it output 160 horsepower, instead of 130. The engine code for the 1967 and 68 911S was "2000S" as opposed to "2000" for the base 911. Top speed was up to 140 mph. The 911S used a Weber carburetor instead of the Solex of the regular 911. Compression ratio was 9.8:1.
The 1967 911S production run was only 1,162 models, so it's a fairly rare car. With 1968 came other new addition, such as a glass rear window for the Targa, and vented brake discs on all 4 wheels. Also new were ventilation slots on the Targa's roll bar. Unfortunately, the 911S was not offered in the US in 1968, but returned in 1969.
In 1969, the 911S gained mechanical fuel injection, and had its power upped to 170 horses. The compression ratio was raised by a hair to 9.9:1. As with all the 911s, the wheelbase was lengthened by 2 inches. The 1970 models received the first major change. Their engine size was increased by 10%, they now held 2.2 liters of volume (2195cc). Power was up to 180 hp at 6,500 rpm. The bore was increased by 4mm to achieve this new displacement. The 1971 911S was unchanged from 1970.
about another engine size increase, now up to 2.4 liters (2341cc). In
both 1972 and 1973, the 911S now had 190 hp at 6,500 rpm. Compression
dropped to 8.5:1.
In 1974, the body was redesigned to meet the new bumper regulations. The new, larger bumpers were body color, and had rubber boots on either side. The engine was again upgraded, now to 2.7 Liters (2,687cc). Horsepower output is now down to 175, due to the exhaust regulations of 1974. Power was down again, in 1975-1977, to only 165 horsepower. During 1975, a special edition "Silver Anniversary 911 S" was offered, for the company's 25th anniversary. In 1978, a new model emerged, the 911 SC.