Along with all the C-series improvements to the 911 line, the 1970 Porsche 911 S was upgraded to include a 180 bhp version flat-6. This further improved the performance credentials of the model which already had Fuchs light alloy wheels and bigger brakes.
2.2 C-Series (1970)
This latest 911 was once again available as either a Coupe or Targa and customers could choose from engines in three alternative states of tune: there was the entry level 125bhp 911 T, the more luxurious 155bhp 911 E or the flagship 180bhp 911 S.
The familiar all-alloy air-cooled Flat 6 with its single overhead camshafts and dry-sump lubrication was bored from 80mm to 84mm. Stroke stayed at 66mm for a displacement of 2195cc (a gain of 204cc over the outgoing unit). Specific to the S model’s engine was a re-profiled camshaft, larger valves, better porting, higher compression and larger jets for the Weber carburetors. This resulted in 30 more horsepower for a total 180 horsepower and torque slightly improved. Redline was raised to 7300 rpm. Porsche fitted an ignition cutout that interrupted spark to the plugs near maximum rpm. One peculiarity of the 911 S was its lack of choke which required accelerator pumping for cold starts was usually enough for starting.
Chassis upgrades included a rear anti-roll bar, Koni shocks and ventilated discs which replaced the standard solid rotors. For the S, special gear ratios were installed in the five-speed transmission including an overdrive in 5th gear. Like the engines, gearbox type numbers were changed from 901 to 911. The higher ratios allowed for 0-60 in 7.8 seconds.
The unitary steel bodyshell shared by all varieties of 911 was now coated with a Tectyl oil-based anti-corrosion fluid. Suspension was fully independent with torsion bars and telescopic shocks fitted all round. The front end used a compact MacPherson strut arrangement with a single lower wishbone while at the rear, semi-trailing arms were installed. For these 1970 model year C-series derivatives, the front suspension mounting points were moved 14mm forward to reduce front wheel castor and lighten the steering at low speeds. Front torsion bar adjustment was made easier on the 911 T and 911 S. Ventilated disc brakes were now fitted across the board.
Also standard were 6 x 15-inch Fuchs forged alloy wheels although 911 Ts destined for certain markets did still come with steel rims. A bigger 62-litre fuel tank was installed underneath the front lid. This was vented on US-bound 911s so fuel vapour could escape. An interesting option for the 911 S during 1970 is that you could order it with a long-range 110-litre fuel tank that left little space for anything else underneath the front lid.
To save weight, aluminium was used instead of steel for the engine cover and the central part of the front bumper on 911 E and 911 S variants. The E and S also had anodized gold badging at the back compared to bare aluminium for the 911 T.
By the end of the 1970 model year, a total of 1,744 911 S Coupe 2.2s were produced, while there were 729 911 S Targa 2.2s made.
2.2 D-Series (1971)
The subsequent 1971 model year D-series 911 came with another series of updates. In the fight against corrosion, bodyshells were now galvanized with a zinc coating applied to exposed underbody areas. Crankcase squirters were introduced to improve piston cooling. There was also a new type of sealed chain tensioner while minor detail alterations were made to the fuel-injection system.
US-spec. derivatives now came with a fuel evaporative control system to prevent the release of vapour into the atmosphere. A heated front windscreen was added to the options list.
For 1971, Porsche sold 1430 coupes and 788 targa, S 2.2s.