How the Honda CVCC met EPA standards without a catalytic converter, and the car that became the Civic
How the Honda CVCC met EPA standards without a catalytic converter, and the car that became the Civic
Posted on February 3, 2016
The Development of the Honda Civic
The forward motion of the automotive industry has long hinged on the advancement of critical technologies – from radical changes related to how engines are designed right down to aerodynamic features that reduce drag and optimize your presence on the road. In this way, Honda has certainly been one of the innovators, leading the pack and showcasing their endeavours to set new standards internally and across the automotive industry.
One such element of advancement comes with the introduction of the CVCC back in 1972. It came about in a time when the world was in financial turmoil – the oil crisis hit and import cars to North America were becoming increasingly more popular and effective. There are those that see this period as a black mark that took years to wipe clean – but, really, if you look at it with a discerning eye you’ll note all the important innovations that emerged from the tumultuous point.
What, exactly, was the CVCC? Well, to get a quick overview of the situation we have to point to the 1955 Air Pollution Act that was passed in United States congress with an overview of Public Health and from which we draw many of the modern pollution laws and standards – as with anything so encompassing, the act has been revised a number of times, but we’ll be focusing on the Clean Air Act Extension applied in the 1970s. Sometimes referred to as the “Muskie Act” the regulations came to have lasting implications for the automotive industry.
Establishing a national standard for carbon monoxide, nitrogen dioxide, sulfur dioxide, particulate matter, hydrocarbons and photochemical oxidants – with some changes applied to further clarify what each meant in respect to industries and individuals.
What this meant for the automakers was an obligatory reduction of 90% emissions across the industry in a five year period. Further exuberating the situation it required that vehicles run on unleaded fuel in a similar time frame.
Associated with this, Congress created a fuel economy regulation – the first such of its kind, in anticipation and connected to the Oil Embargo of 1973.
Enter the “Compound Vortex Controlled Combustion” (CVCC) created by Honda to reduce emissions which began development earlier but is mentioned directly in 1971. Technologically, the device was intended to create lean combustion via a prechamber and was tested in a single-cylinder 300 cc Honda EA engine used on the N600 Hatchback.
What it accomplished was remarkable: Not only did it negate the need for a catalytic converter, but it also met the United States emissions standard with ease. A brilliant piece of technology, the smaller intake on the CVCC sat between the spark plug and actual cylinder, receiving rich fuel/air mixture and enabling a cleaner burn when the spark plug fired.
Introduced in the Honda Civic, sales figures at the time of launch doubled in 1974 to 1975 alone. The technological innovations that the CVCC brought to drivers have led to ever-more efficient vehicles and cleaner burning features – placing the CVCC as one of the more important additions to the automotive industry – especially those things that it inspired – of the 1970s as well as positioning Honda in its current, globally-influencing status.