Honda C engine

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Honda C30A

Honda's first V6 engines are members of a single family, the C-series. It is a 90° V6 design and is being phased out in favor of the newer 60° J-series.


The SOHC C20A is a 2.0 L version, producing 145 hp (108 kW). This was the first Honda V6 engine.

Applications; non-North America:

The C20AT was a turbocharged version, producing 190 hp (140 kW).

Applications; non-North America:

  • 1989 Honda Legend
      • NOTE: Honda made a "Wing-Turbo" Legend marketed under the Honda name and was only available in the Japanese Domestic Market. The turbo was used on C20AT engines and are extremely rare. The turbocharger used was a Variable Geometry turbo that Honda developed. The turbo used aerofoil style flappers all around the turbine housing. These "Wings", as Honda called them, were controlled by vacuum and by the Legend's ECU and they were constantly adjusted. Basically, at low speeds the wings would be nearly closed to speed and direct exhaust pressure precisely on the turbine wheel. At cruise speeds, the wings would be open and it would act like a much larger turbo to increase fuel economy. This car was really quick and really powerful, but the price premium over the standard Legend was too much for most so the car disappeared. This was one of the only production Hondas ever turbocharged from the factory, along with the new Acura RDX and the older Honda City's.


The SOHC C25A is a 2.5 L version, producing 165 hp (123 kW).

Applications; North America Only:


The SOHC C27A is a 2.7 L version, producing 170 hp, (127 kW).

Applications; non-North America:

Applications; North America:


The DOHC VTEC C30A is a 3.0 L version, producing 201 kW (270 bhp) and 285 N·m (210 ft·lbf) of torque. The engine was the first in the US to utilize Honda's proprietary VTEC variable-valve timing system, which adjusts cam lift and duration depending on engine RPM and throttle position. VTEC allows the C30A to produce a high maximum power level while maintaining a relatively flat torque curve.

The C30A also made use of titanium connecting rods, which was another first in a mass-production vehicle. The lightweight rods allowed a higher RPM to be achieved while maintaining the strength of traditional steel rods. The C30A block is an open-deck design made from an aluminum alloy with cylinders sleeved in ductile iron. The heads are a twenty-four valve, dual-overhead cam (DOHC) design and contain the VTEC mechanism, which is actuated by oil pressure. For maximum performance, the C30A uses a direct ignition system, with individual coils positioned directly over each cylinder spark plug.

Due to its DOHC layout and its lighweight rotating assembly, the C30A is capable of reliable high RPM operation. Factory redline is 8000RPM and balanced/blueprinted versions of the engine can easily reach 9000RPM with little to no reliability issues.

Due to its complexity, cost and use of exotic materials, the C30A was used exclusively on Honda's NSX supercar. For NSX's equipped with a 4-speed automatic transmission, Honda used a slightly less powerful version of the C30A, which utilized less aggressive cam timing and produced 252 bhp.

An advanced version of this engine exists (though not in a production form) that campaigned briefly in the 2004 Japanese SuperGT racing series (see All Japan Grand Touring Car Championship) by the factory-supported Team Honda Racing group in highly modified GT-spec NSXs. This engine has various upgrades and modifications by M-TEC (formerly Mugen) and is the first turbo-charged Honda engine used in the series (prior to 2003, the GT-spec NSXs used a highly advanced, naturally-aspirated variant of the C32B engine). Though the exact performance figures are kept secret, it is rumored to output more than 500 bhp.


  • 1991-1996 Honda NSX 5-Speed Manual Transmission
  • 1991-2005 Honda NSX 4-Speed Automatic Transmission


The C32A is a 3.2 L version. The SOHC depending on model year, produces 200 and 230 hp (175 kW).

Applications; North America Only:


The C32B is a highly tuned DOHC V6 used in the Honda NSX, which produces 290 hp (216 kW) and 224 lbf·ft (304 N·m). The engine is essentially an update to the C30A and does not share commonality with the C32A. Honda increased displacement to 3.2 L (≈195 cu in) through the use of larger 92 mm (3.6 in) pistons over the 90 mm (3.5 in) used in the C30A. To accommodate the larger pistons, Honda used and advanced metallurgical technique on the cylinders called Fiber Reinforced Metal (FRM), in which an ultra lightweight alumina-carbon fiber is cast into the traditional aluminum alloy for enhanced rigidity. This process allowed thinner cylinder walls to be used while providing acceptable cooling characteristics. The C32B also used 32 mm (1.3 in) intake valves, which are 1 mm (0.04 in) larger than those in the C30A.


  • 1997-2005 Honda NSX 6-Speed Manual Transmission


The C35A is a SOHC and carries the largest displacement of the C series at 3.5 L (≈214 cu in).


See also