Mercedes-Benz C111/II
Mercedes-Benz C111/II at the Mercedes-Benz Museum
Overview
ManufacturerDaimler-Benz
Production1970 (16 cars produced)
AssemblyUntertürkheim
DesignerBruno Sacco
Body and chassis
ClassSports car
Body style2-door berlinetta
LayoutLongitudinal, Rear mid-engine, rear-wheel drive
DoorsGullwing doors
Powertrain
Engine
  • C 111 I: M 950 F (3-rotor Wankel, 3,600 cm³[1]
  • C 111 II: M 950/4 (4-rotor Wankel, 4,800 cm³[1]
  • C 111 II-D and III: OM 617 (5-cylinder Diesel, 3005 cm³[2])
  • C 111 IV: M 117 (V8 Otto, 4500 cm³[3])
Power output
  • M 950 F: 205 kW (275 hp) at 7000 rpm[1]
  • M 950/4: 260 kW (349 hp) at 6000 rpm[1]
  • OM 617: 140 kW (188 hp) at 4200 min−1[2]
  • OM 617: 170 kW (228 hp)[4]
  • M 117: 368 kW (493 hp)[3]
Transmission5-speed manual
Dimensions
Wheelbase2,620 mm (103 in)
Length4,440 mm (175 in)
Width1,800 mm (71 in)
Height1,120 mm (44 in)
Chronology
PredecessorMercedes-Benz SL-X
SuccessorMercedes-Benz CW311
Mercedes-Benz C112
Suspension layout of the Mercedes-Benz C111 with independent multi-link on the rear axle
C 111-II
C 111-III
C 111-IV

The Mercedes-Benz C111 was a series of experimental automobiles produced by Daimler-Benz in the 1960s and 1970s. The company was experimenting with new engine technologies, including Wankel engines, diesel engines, and turbochargers, and used the basic C111 platform as a testbed. Other experimental features included multi-link rear suspension, gull-wing doors and a luxurious interior with leather trim and air conditioning.

History

The first version of the C111 was completed in 1969, and presented at the 1969 IAA in Frankfurt. The car used a fiberglass body shell and with a mid-mounted three-rotor direct fuel injected Wankel engine (code named M950F). The next C111 appeared in 1970; it was shown at the 1970 Geneva International Motor Show. It used a four-rotor engine producing 260 kW (349 hp).[1] The car reportedly could reach a speed of 300 km/h (186 mph).[5]

The company decided not to adopt the Wankel engine and turned to diesel experiments for the second and third C111s. The C111-IID's engine was a Mercedes-Benz OM 617, and produced 140 kW (188 hp) at 4200 min−1. It was based on the Mercedes-Benz 85 kW variant of the OM 617 used in the Mercedes-Benz W 116 S-Class, but had a different turbocharger without a wastegate, which allowed an increased pressure ratio of 3.3. Daimler-Benz also added an intercooler that significantly improved the engine's thermal efficiency.[2]

The C 111 III prototype that was completed in 1978, had a more aerodynamic bodywork that gave it an air drag coefficient of 0.195. It had a modified 3-litre version of the Mercedes-Benz OM 617 five-cylinder Diesel, now producing 170 kW (228 hp), and a BMEP of 1.68 MPa, resulting in a maximum torque of 401 N·m at 3600 min−1. It enabled the C 111 III to reach a top speed of 338 km/h (210 mph) at the Nardò Ring in 1978, and also to average a 16 l/100 km fuel consumption at an average speed of 325 km/h.[4] The engine was fitted with an M-type inline injection pump of Bosch's PE series with a maxium injection pressure of 40 MPa.[6]

A later 4.5 L twin KKK-turbocharged V8 version that produced 368 kW (493 hp; 500 PS) at 6000/min[3] set another record, with an average lap-speed of 403.78 km/h (250.958 mph). This was achieved by Hans Liebold in 1 minute, 56.67 seconds on May 5, 1979.[7]

Total production was 16 cars: 13 first and second generation Wankel engined cars, two diesel engined third generation cars used in the Nardò record attempt, and a single V8 engined fourth generation car.[8]

Mercedes-Benz introduced the C112 at the Frankfurt Motor Show in 1991 as a proposed production sports car. The car used a mid-mounted 6.0 L V12 engine. After accepting 700 deposits, the company decided not to proceed with production.

References

Notes

  1. ^ a b c d e Bensinger, Wolf-Dieter [in German] (1973). Rotationskolben-Verbrennungsmotoren (in German). Berlin, Heidelberg, New York: Springer. p. 143. ISBN 978-3-540-05886-1.
  2. ^ a b c Zinner, K. (1980). Aufladung von Verbrennungsmotoren (in German) (2 ed.). Berlin/Heidelberg: Springer-Verlag. p. 294. ISBN 978-3-662-11204-5.
  3. ^ a b c Andreas Of-Allinger, Lilly Wöbcke (2020-03-20). "50 Jahre Mercedes C111: Design-Studie mit Wankelmotor". auto motor und sport (in German). Retrieved 2023-11-26.
  4. ^ a b Reif, Konrad (2012-02-23). Klassische Diesel-Einspritzsysteme (in German). Wiesbaden: Springer. p. 51. ISBN 978-3-8348-8664-4.
  5. ^ "Mercedes-Benz C 111". www.mercedes-benz.com.
  6. ^ Reif, Konrad (2012-02-23). Klassische Diesel-Einspritzsysteme (in German). Wiesbaden: Springer. p. 52. ISBN 978-3-8348-8664-4.
  7. ^ "Storia - Nardò Technical Center". Home - Nardò Technical Center (in Italian). Retrieved 2019-07-06. Con un motore biturbo V8 da 4,82 litri e una potenza di 373 kW (500 CV) a 6.200 giri/min, la Mercedes-Benz C111-IV raggiunge la velocità di 404 km/h. Con questa vettura l'ingegnere capo Hans Liebold percorse il "giro lanciato" sul circuito di Nardò in 1:57 min.
  8. ^ "1970 Mercedes-Benz C111-II - Jay Leno's Garage". Archived from the original on 2021-12-13 – via www.youtube.com.

Bibliography

  • Clarke, R.M., ed. (1987). On Mercedes 1963-1970. Road & Track Series. Cobham, Surrey, UK: Brooklands Books. ISBN 1-869826-41-8.
  • ——————, ed. (1980). On Mercedes Sports & GT Cars 1970-1980. Road & Track Series. Cobham, Surrey, UK: Brooklands Books. ISBN 0907073395.
  • Frère, Paul; Weitmann, Julius (1981). Mercedes-Benz C111: Experimental Cars. Lausanne: Edita. ISBN 2880010977.
  • Kalbhenn, Wolfgang; Heidbrink, Gerhard; Hack, Joachim (2021). Mercedes-Benz C111: Fackelträger, Traumsportwagen und Rekordjäger [Mercedes-Benz C111: Torchbearers, Dream Sports Cars and Record Hunters] (in German). Stuttgart: Motorbuch Verlag. ISBN 9783613041370.
  • Wirth, Thomas (2012). Mercedes-Benz Supercars: From 1901 to Today. Atglen, PA, USA: Schiffer Publishing. ISBN 9780764340901.