Porsche Carrera 2.7 / G And H 1974 - 1975
The Carrera 2.7 was mechanically identical to the 1973 RS, inheriting its 210 bhp (154 kW) MFI engine and still weighed the same at 1075 kg (2370 lb). It had the wide RS rear wings and also the ducktail for the 1974 model (except for the German market).
It was available either as a coupe or a Targa. For 1976 a special run of 113 coupes with MFI were made. In addition 30 MFI Targas with narrow rear wings were made for the Belgian police.
The US Carrera 2.7 was restricted to the 2.7 K-Jetronic engine as the MFI RS engine was banned on emission grounds. Power output was 175 bhp, later being reduced to 165 bhp, and in California 160 bhp.
The well known problem of pulled cylinder head studs with the K-Jetronic 2.7 engine only occurred in hot climates. This emerged in 1975 in California where thermal reactors, aimed at reducing emissions, were fitted below the cylinder heads thus causing heat build up around the magnesium crankcase and then made worse by the lean running K-Jetronic CIS. The fitting of a 5-blade engine fan instead of the usual 11-blade further compounded the situation. Bearing in mind Porsche's largest market being the USA, the 930 Turbo, Carrera 3.0 and all subsequent models used aluminium alloy crankcases which were around 15 lb (7 kg) heavier.
The Bosch K-Jetronic CIS varied fuel pressure to the injectors dependent on the mass airflow. While this system was exceedingly reliable, it did not allow the use of as "hot" cams as MFI or carburettors allowed. Therefore, the 911S's horsepower decreased from 190 to 175 PS (140–128 kW) despite the displacement increase from 2.4 to 2.7 L. However, the engine did have increased drivability.
Also produced for the 1976 "model year", for the U.S. market, was the 912E, a 4-cylinder version of the 911 like the 912 that had last been produced in 1969. It used the I-series chassis and the 2.0 Volkswagen engine from the Porsche 914. In all, 2099 units were produced. In 1976 the Porsche 924 took this car's place for the 1977 "model year" and beyond. The power was supplied by a 4-cylinder high-performance fuel injection motor also used in the 411 Volkswagen. Less than 6000 were built.