Although Honda has used the pre-chamber ignition technology on Honda cars in the 1970s, the technology is now standard on most Formula 1 engines. But the highly efficient and performance-oriented technology has not been used on motorcycles. Honda has now patented a new pre-chamber ignition system for Honda motorcycles that will not only allow the manufacturer to squeeze out more horsepower per litre but also improve the fuel efficiency as well make the engine cleaner by reducing its emission.
For the uninitiated, the pre-chamber ignition technology comes in two forms – Active pre-chamber and passive pre-chamber. According to the leaked images, Honda’s pre-chamber technology appears to be the Active type, but Honda has incorporated a rotating pre-chamber and feature dual-stage injectors. The rotating pre-chamber contains a fuel injector and a spark plug and another fuel injector is located on the side of the cylinder head that spray’s fuel into the main combustion chamber.
The system works by spraying a lean air/fuel mixture into the main combustion chamber which is then compressed by the piston. The leaner mix will not be able to ignite with the spark plug so another fuel injector sprays a rich mix into the pre-chamber a dedicated space separated from the main chamber. A spark plug then ignites the fuel in the pre-chamber and jets at the bottom of the pre-chamber spew streams of fire into the main combustion chamber igniting the leaner mixture producing a larger explosion.
The ignition system also helps the engine achieve a stoichiometric mixture which is 14.7:1 which means for every one gram of fuel there are 14.7 grams of air in the mix. This highly improves the ability of the catalytic converter system in the exhaust gas treatment system, reducing the number of harmful gasses making even high-performance cars adhere to the suffocating new emission norms.
The latest high-performance road car to use the pre-chamber system is the Maserati MC20 which features the ‘Nettuno’ power unit which uses a Formula 1 engine derived pre-chamber combustion chamber with high-pressure direct injection where the fuel supply is pressurised to over 5000 PSI and an 87 PSI Port (indirect) injection system. The system helps produce a specific power output of 210 PS/litre. The MC20 produces 630 PS of power from a 3.0-litre V6-cylinder engine all while conforming to EU6D, China 6B and Ulev 70 emission norms.
Honda could call its pre-chamber technology CVCC (Compound Vortex Controlled Combustion) as it used to when the technology was patented in the 1970s.