1980 Porsche 935J

Porsche introduced the 935 Group 5 racer in single-turbo form in 1976 and raced successfully in international competition until the arrival of the new Group C category in 1983. During that period, the 935's engine output increased from 485 hp of the original single-turbocharged factory cars to over 800 hp of some of the later twin-turbo 935 variants built by various race teams in the 1980s.

German automotive engineer Norbert Singer was instrumental in every one of Porsche's 16 overall race victories between 1970 and 1988 at the 24 Hours of LeMans. He was tasked with developing the 911 road car for racing, and that included the 935 project. Under his direction, the 935s were built atop strengthened 930 Turbo body shells and given a more aerodynamic fiberglass reinforced plastic slant-nose with the headlights mounted in the large front air dam. The rear quarters were widened to accommodate the larger wheels and tires needed to send the extra power of the turbocharged engine to the road. Uprated center-lock hubs were fitted for quick wheel changes. A locked-up spool differential was fitted, along with a biplane tail, which also helped to keep the rear of the 935 planted to the pavement.

The torsion-bar suspension of the 911 was replaced with coil-over struts and shocks, and multi-adjustable anti-roll bars. Ventilated and cross-drilled disc brakes developed from the Porsche 917 prototype provided the stopping power.

The Porsche 935 would claim victory at the 1979 24 Hours of LeMans, and other major endurance races, including Daytona, Sebring, and the 1,000 km Nurburgring. Of the 370 races the 935 was entered, it won 123.

With rule changes coming in 1982, Porsche did not officially enter in 1979 or 1980, and the last customer cars were built early in 1979. Porsche did offer support to customer racing efforts with the 935, 936 and the old 908 and 917, mostly in the form of spare parts, body-shells and engines. With the spare parts, some teams built up complete cars, including the Joest Racing and the Kremer Brothers. To keep them eligible for racing, they were still referred to as Porsche 935s.

In 1982, the FIA discontinued Group 5 competition. The 935 continued its racing career in the IMSA GTP category. They continued to race until 1986, though their racing career had ended in 1984. Privateers entered the car in 1985 and for two races in 1986.

by Daniel Vaughan | Feb 2020