www.QV500.com - Porsche 911 (1974 - 77) Part 11: 934
 

Replacing the enormously successful 3-litre RSR campaigned so effectively by privateer teams, Porsche's 934 was the firms latest Group 4 customer race car. The factory squad would be busy campaigning a pair of crack Group 5 935's in 1976, leaving the lower category open to the satellite Porsche teams who were up against an admittedly weak opposition, particularly in Europe. Here, the odd turbocharged Stratos was no match for the hoardes of 934's while in the US, Chevy Monza's, Camaro's and Corvette's would only occasionally put up more of a fight.
   

Based around Porsche's production 930, the 934 weighed in at 1120kg, just 20kg less than the stock model. This was because the Typ 930/50 3-litre motor that had been homologated in the H-series 911 Turbo was classed on the basis of its swept volume equivalency of more than 4-litres. Cars of between 4 and 4.5-litres had a minimum weight requirement of 1120kg, allowing Porsche to strip 934 right down and then strategically reposition the ballast to bring it back up to weight. Some parts inevitably stayed though and these often included stock door trim and even electric windows. More importantly, 934's were equipped with fully-adjustable suspension and anti-roll bars plus cross-drilled and ventilated discs with finned calipers. 16-inch BBS alloys were fitted along with a 32-gallon fuel cell under the front lid. The new Typ 930/75 turbocharged engine used a standard engine casing, crank, connecting rods and cylinder heads while at 2993cc, displacement was unchanged from the road car, as was compression at 6.5:1. With new pistons and water cooling for the air passing between the KKK turbocharger to the induction, output rose to 485bhp at 7000rpm. This was running at 1.3bar, however, well in excess of 500bhp was available with a little more boost. A complex twin Behr intercooler arrangement was housed in the deep front spoiler and allowed the engine to run more efficiently and reliably, revised Bosch K-Jetronic injection, larger intake ports and a reinforced four-speed gearbox also being added.
 
All this equated to some awesome performance figures, 0-60 requiring just 3.9 seconds while a top speed approaching 190mph was possible. Anyone who ever raced one will tell you the 934 was an exciting car to drive, its power, high weight and relatively skinny tyres making for some hairy moments. The largely standard steel shells were equipped with lightweight glassfibre wheelarch extensions, doors, engine covers and front lids. At the front a distinctive apron housed five gaping air intakes to feed the central oil cooler, twin Behr water radiators and brakes.
   
This would be the last 911 racer to retain some semblance of the original shape for many years. Those curvaceous front wings and the exposed sloping tail were heavily modified for subsequent customer cars, namely the more aerodynamically extreme Flat-Nosed 935. The prototype was completed in September 1975 and tested extensively around Europe where it proved considerably faster that its predecessor. 31 934's were built, but even as early as spring 1976, the factory were providing owners with the opportunity to transform their vehicles into 934/5's. This could be done either by Porsche or the privateer teams themselves, the 934/5 upgrade pack including wider wheels and a split-level rear wing normally good for a couple of seconds per lap. In 1976, 934's dominated most series they contested, the prestigious World Manufacturers and Trans Am Championship's both falling its way. Developments for 1977 saw the arrival of a new IMSA-spec 934, ten of which were produced with 934/5 wheels and wings. Also featuring new Typ 930/73 flat six motors, output rose to 540bhp at 7000rpm thanks to the adoption of mechanical rather than electronic fuel injection. 1977 proved to be another good year and with IMSA now allowing turbocharged cars to race, Porsche added this series to their ever expanding resume. World Manufacturers and Trans Am titles were again secured in 1977 along with a class win at the Le Mans 24 Hours, this feat being repeated at the French classic in 1979.