The Sauber C9 (or Sauber-Mercedes C9 and 1990 Mercedes -Benz C9 ) was a Group C racing car used from 1987 to April 1990 in World Sportscar Championship ( WSC) and the 24- hour race at Le Mans been. He loosened his predecessor, the Sauber C8, from.
Built in 1987 as a successor to the C8 and as a continuation of the partnership between Sauber and Mercedes- Benz denied the C9 his first season in the sports car world championship among Kouros Racing a perfume brand Yves Saint Laurent. Officially supported by Mercedes -Benz, the team only reached the twelfth. At Le Mans, both cars failed. For 1988, the namesake and sponsor Kouros got out, whereupon the team Sauber-Mercedes was renamed. With AEG- Olympia as a sponsor it reached the second place in the sports car world championship behind Silk Cut Jaguar team with five wins. However, the 24-hour race at Le Mans, the team suffered a setback. Because of punctures in training Sauber took the car back.
With seven wins in eight races, the team won the World Sports Car Championship season in 1989. 's Qualification for the 24 - hour race at Le Mans C9 reached on the Mulsannegeraden a speed of 389 km / h, until then second highest rate, here ever achieved by a WM P88, whose engine was destroyed by lack of cooling in this action. In the race, Manuel Reuter, Jochen Mass and Stanley Dickens won the Sauber -Mercedes C9 the race with a distance traveled of 5265.115 km. Second was the Sauber-Mercedes C9 by Mauro Baldi, Kenny Acheson and Gianfranco Brancatelli, the third Sauber-Mercedes finished fifth.
For season opener of the 1990 World Cup on April 8 at Suzuka started the C9 one last time in a race - now as Mercedes -Benz C9 - and ended it with a double victory.
Six Sauber C9 were built (two per 1987, 1988 and 1989). 1987 and 1988 they were painted dark blue, according to the official activities of Mercedes -Benz but silver since early 1989.
The behind the driver mounted engine ( mid-engined ) of C9 was initially an evolved for racing V-8 cylinder, type M 117, with light alloy cylinder block, which was used since 1969 in the series sedans from Mercedes -Benz. This unit had as the standard engine driven by a timing chain overhead camshaft per cylinder bank and two valves per cylinder. In racing engine, the cylinders were Nikasil coated running surfaces and had oil cooled pistons. Titanium parts reduced the weight by twelve kilograms. A special crankshaft with counterweights, which should allow a speed of 9000/min, was not used.
In 1989, the M117 engine was replaced by the M119 with four valves and two camshafts per cylinder bank. With this engine, the maximum torque increased from 810 to 825 Nm, and the pressure of the turbocharger could be briefly increased to 1.2 bar, which in qualifying a power output of up to 590 kW ( 800 hp) was available.
Due to the Group C regulations could be a maximum of 51 liters per 100 kilometers, the driver demanded full attention to get the necessary power in any situation, on the other hand but not to exceed the consumption limit of consumption.
Chassis, chassis and body
The chassis of the C9 is a Aluminiummonocoque that weighs just 48 kg. The wheels are suspended from twin A-arms, each with a spring -damper unit. The rear coil springs and shock absorbers are mounted longitudinally lying horizontally and act on reversing lever on the suspension. This arrangement was due to the particular shape of the body required by the then-common Ground effect was achieved, which increased the contact pressure of the vehicle on the roadway.