Kremer Porsche 935 K4
The ultimate expansion stage
The ultimate expansion stage of the 935, at least for the Kremer team, was reached with the 935 K4 for the 1981 season. Already in 1980 the development of the new project started in the underground car park of the Robert-Perthel-Straße in Cologne. The impetus for the project of a 935 with a lattice tube frame was the Zakspeed-Capri. Manfred Kremer remembers: The idea of a pure tubular lattice car came to us when we saw how successful the Capri was.
The advantages of such a car were that it had a stiffer and lighter chassis, with a lower centre of gravity and better weight distribution options. Kremer first created a model of a possible wire frame. In order to comply with the regulations, the body of a 911 was measured and the frame adapted to fit the original shape. The resulting data was converted into the model and converted to a scale of 1:1 on the straightening plate.
The body and aerodynamics of the K4 were designed together with the long-time friend and partner Ekkehard Zimmermann and his company DP. While Bob Wollek drove the first races with the 1980 935 K3 in the 81st season, the K4 got its final polish in Cologne. Wollek showed the potential of the new car during the race in Wunstorf, where he changed from the K3 to the K4 and immediately entered the Top 5.
Unfortunately the career of the 935 K4 ended already after one year due to the group C regulations in 1982 and the end of the group 5 category.
Technical data GT1
Group 5, Division I over two litres displacement
Season: Half of the 1981 season
Number of pieces: 2
Engine: Six-cylinder 4-stroke boxer engine, air-cooled
Transmission: synchronized Porsche four-speed racing transmission
Differential: rigid axle through drive
Chassis: Aluminium tubular frame
Body: wide front and one-piece rear section, hoods, doors and mudguards made of carbon fibre / GFK-composite
Compressed: 6,3:1 to 7,0:1
Power: max. 596 kW (810 PS) at 8000 rpm
Max. Torque: 750 Nm at 5500 rpm
Supercharging: two KKK exhaust gas turbochargers (Kühne,Kopp,Kausch) K26 with intercooler water and air
boost pressure: 1,3 bar, adjustable by driver up to 1,8 bar
Chassis: independent front suspension and continuously adjustable stabilizers from the driver's seat
rear: welded light alloy suspension arms and infinitely adjustable stabilizers from the driver's seat
Brakes: Porsche Monobloc four-piston fixed calipers, diameter 304 mm
The brake force distribution can be adjusted while driving using the handwheel.
Wheels: BBS, three-piece; rim spider: cast magnesium, rim flange: aluminium
front 11 x 16"
rear 14,75 x 19"
Unladen weight: 1025 kg
maximum speed: at longest gear ratio approx. 300 km/h