www.QV500.com - Porsche 911 (1978 – '83) Part 3: 911 3.3 Turbo K, L, A, B & C-series
 

After entering production in early 1975, Porsche's flagship 3-litre 911 Turbo had carved itself a reputation as one of the worlds most capable supercars. For the 1978 model year, Porsche introduced an improved 3.3-litre version. Designated Typ 930/60, the new engine was enlarged to 3299cc thanks to a bore and stroke of 97 x 74.4mm respectively. Compression was also increased (now up to 7.0:1 from 6.5:1) and although the Bosch K-Jetronic was unchanged, output leapt by 40 horses to 300bhp at 5500rpm. This sizeable gain in output was also partly down to a larger yet lighter KKK turbocharger.
   
Moreover, an air-to-air intercooler was adopted (rather than water-to-air), just like on the spectacular 935. Mounted 30mm further back because of a bulkier Porsche-designed clutch disc hub, the 3.3-litre engine propelled these cars from 0-60mph in 5.3 seconds and well beyond 160mph. They were all fitted with the 917-derived cross-drilled and ventilated discs with aluminium hubs and finned four piston alloy calipers. This redressed perhaps the biggest criticism of earlier 911 Turbo's and these second generation variants could stop as well as they went. However, North American clients weren't so lucky for although they also got the 3.3-litre motor, it was again subjected to various emissions add-ons that strangled output to 265bhp at 5500rpm. Although all turbocharged motors were fitted with an air pump to reduce exhaust emissions regardless of their destination, the ‘49-state' Typ 930/61 versions featured thermal reactors whilst California bound Turbo's were further burdened by a vacuum control. While on the subject of different specifications for different markets, it's also worth noting that right-hand drive examples were finally fitted with the Hydrovac brake servo that had been present on left-hand drive examples since late 1976. Outside, the only visual alteration introduced from K-series Turbo's onwards was a bulkier rear wing. Housing that new air-to-air intercooler, the 3.3 was identifiable thanks to thicker matt black side pods either side of the rubber aerofoil. Going into production during September of 1977 (for the 1978 model year), the 3.3 Turbo instantly eclipsed its predecessor, press and public both raving about the increased performance, not least the improved brakes. Only available as a Coupe, 1257 K-series Turbo's were produced before being replaced by the 1979 model year L-series in September '78.
 
Porsche made no significant alterations for '79 and 2052 were completed. Few major changes were made for the 1980 model year Turbo either, arguably the most significant development having been its withdrawal from the US and Japanese markets when A-series production got underway in September 1979. Sales continued unabated around the rest of the world, these 1980 model year Turbo's having been identifiable via twin rather than single exhaust pipes. 840 were completed. Thereafter, 1981 and '82 model year Turbo's were practically unchanged, 761 and 1027 being constructed respectively.