Honda Civic Fuel Economy: Engine Technology Promotes Fuel Efficiency
We take a look at the Honda Civic’s MPG progression over its lifespan and break it down here.
The Honda Civic has been at the forefront of best mpg since its launch in the US in 1972, recording an impressive 39 miles per gallon on the highway and 27 in the city. How do these fuel economy numbers compare to a modern 2021 Civic? They’re actually not much better at first glance, averaging 32 mpg in the city and 42 on the highway.
But the Civic has also grown more than three feet long, nearly a foot wide, and nearly doubled in weight over its 50 years. To accommodate the natural evolution of the Civic, Honda had to make not only a more efficient engine but also a more powerful one.
Below, we’ll cover the history of the Honda Civic and review some notable technological advances that made it the famous fuel pump it is today.
CVCC Engine: Fuel-efficient power
There’s a common misconception about the famous HVAC engine that it’s something of an origin story for the Honda Civic, but what it actually represents is much more interesting. The CVCC, or “compound vortex-controlled combustion” engine, was the Japanese automaker’s attempt at innovation that the world had never seen. Japan faced emissions problems similar to those of the United States in the 1970s.
The founder of the Honda Motor Company, Soichiro Honda, created a research department to study and understand emissions in order to find a simple solution. Catalytic converters at the time were bulky and inefficient, so Honda was looking for something that would work without the need for a new emissions device.
Even the name “Compound Vortex Controlled Combustion” was left intentionally vague because the patents didn’t quite solidify for Honda. Announcing this technology before it was ready was a strategic move by founder Soichiro to motivate employees to feel the pressure of the project. What they found was incredible for the time.
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The CVCC fuel system was designed to run very lean and beyond the ideal 14.7:1 air/fuel mixture seen in most cars. When you are running a significantly lean engine, you are less likely to get contaminated, unburned fuel.
Because the engine burns all the fuel in the combustion stroke of a four-stroke engine, the problem becomes a spark because you now have too much air mixed with your small dose of fuel, making everything harder to ignite.
While Honda tried to solve its problems with experimental spark plugs and intake ports that generate larger air swirls, it ultimately continued to fail. Further brainstorming revealed an idea based on existing diesel technology, in which there would be a pre-chamber that would ignite the air-fuel mixture.
In this smaller chamber, a flame would start and eventually ignite the larger mixture left in the cylinder. The result was great. Emissions were clean enough in early Civics to completely avoid the use of expensive catalytic converters.
This led to even lower production costs, and Honda ultimately earned the highest 1975–1978 EPA fuel economy ratings for its first-generation Honda Civic. Ultimately, emissions requirements were tightened further, forcing Honda to join competitors using catalytic converters.
Honda Civic engines: Lean Burn system technology
By 1979, Honda had continued to fine-tune the CVCC engine they used in their Civics. With each trim level using a CVCC, Honda added a third valve per cylinder, which paved the way for lean burn system technology. This allowed Honda to increase the air/fuel mixture up to 22:1 by controlling where the fuel and air flowed into the cylinder and at what time.
Combined with the pre-chamber we explained above, the engine could achieve up to 33 mpg in the city and 45 mpg on the highway, an incredible feat for the late ’70s.
The 1980s brought new technologies for Honda, and in 1983, Every Breath You Take by Police was on all radio stations in America. Honda would finally introduce its well-known and long-lived D-series engine along with a new 1.5-liter CVCC engine.
At its peak, the 1986 Honda Civic Coupe HF (High Fuel Economy) achieved 52 mpg city and 57 mpg highway thanks to its new and improved 1.5L CVCC engine. In 2008, revised testing would reduce the actual number to a respectable City 42 and Highway 51. The Civic “Panera” years would come to an end and open the door to a new shape.
The redesign of the Honda Civic and the launch of VTEC
The redesign of the Civic in 1987 for the 1988 model year was a totally radical new direction. With larger interior space, a lower overall profile, and still industry-leading miles per gallon, it made sense for consumers to take a look at the Civic.
Honda also introduced the famous B18A DOHC VTEC engine, Honda’s first variable valve timing and electronic lift control (VTEC) engine. This B-series platform would be used in several Hondas in addition to the Civic until the early 2000s.
Honda saw fuel savings in the 1950s with its high-fuel economy Civics and in the 1940s for other applications. Sportier models like the Honda Civic Si suffered, with a combined fuel economy of 23 miles per gallon, at a small cost to the pleasure of shifting gears.
The redesign of the Civic in the early ’90s was not in vain. Its fuel economy for the VX saw a combined fuel economy of 51 mpg.
In September 1991, Honda continued to develop its own technology and further pushed the boundaries with an emphasis on a more aerodynamic body style for the Civic. The redesign of the early ’90s model was not in vain, as the Civic’s fuel economy for the VX sedan (the replacement for the HF) saw a combined fuel economy of 51 miles per gallon.
While the D15 engines guzzled gas, the D16Z6 VTEC guzzled it in the Si model, a common theme for fun. The Si would only achieve a combined 32 mpg, despite a 9,000 rpm tachometer and 7,200 rpm redline. Honda not only focused on fuel economy but also combined fuel economy and decent performance.
when the 90s rolled around for Honda, they had made it clear that they were building slightly different cars. With eight different trim levels, including the HX, which was designed for better fuel efficiency, and the GX which ran on natural gas, it was clear that Honda was trying every possible angle to squeeze a few more miles per gallon out of its platform. . .
Looking back, it’s truly amazing what they were able to accomplish. The fuel-efficient HX, which only came in a coupe, was the only model of this generation with a CVT (continuously variable transmission), and managed a remarkable 33 mpg city and 38 mpg on the highway.
New lows, new highs
Unfortunately, Honda handled the most recalls it has ever had for any generation of Civic during the seventh-generation model year. Notably, the transmission problems not only affected Civics but also spread to other models, including the Honda Accord.
There has been a major failure with the automatic transmission’s torque converter, which manages the connection between your engine and transmission. In 2004, Honda settled a class-action lawsuit and recalled older model Civics, but none of the recalls included the 2001 model year, leaving owners to fend for themselves.
On the other hand, the seventh-generation Honda also houses the first hybrid Civic, a bold step forward executed at precisely the right time. Keep in mind that at the time, the Toyota Prius was the king of the electric vehicle market, so when the Civic Hybrid tied it for third place on the American Council for an Energy-Efficient Economy’s list of “most “green” all eyes were on the Civic.
Honda recovers with the eighth generation. Civic
With transmission problems persisting through most of the seventh-generation model cycle and the class-action lawsuit looming, Honda needed a win and to put some distance between itself and the black mark of unreliability. The eighth generation was proof that they did not give up.
The automatic transmissions caught up to the manuals in terms of miles per gallon, and some trim levels even surpassed them with a respectable 35 mpg combined. Released for this model cycle, the R16A engine achieved a reliable and smooth 140 horsepower.
Honda’s Civic Si for the eighth generation produced 197 horsepower from its K20Z3 engine and could only achieve 32 mpg on the highway. That barely beat the city mpg figures of the cheaper Civic, showing that the performance penalty would continue.
Despite the history, Civic sales for the 2006-2010 Civics were strong. Honda was back on top.
Honda Civic Sales
At the end of the 2011 model year, the Honda Civic took over some of Honda’s other vehicles, with Americans choosing a pickup truck, a Toyota Camry, or some SUV.
In fact, the Honda Civic was the 12th best-selling vehicle in the United States behind Japanese trucks, SUVs, and midsize cars, including Honda’s own Accord. The Civic had a maximum attainable mpg of 26 city/34 highway, which was not its best year.
With more than 1.5 million Civics sold in the ninth-generation model cycle, something big was on the horizon for the Civic brand. Only this time it would be something totally different.
The redesign of the Honda Civic
In 2015, Honda launched a completely and aggressively redesigned Civic that looked completely different than anything it had done before. This global overhaul was accompanied by higher quality steel construction, lower center of gravity, “c” shaped taillights, and LED daytime running lights that highlight the style in a fresh new way. The Civic now achieved consistency across all trims at 31 mpg in the city and 42 mpg on the highway.
The Si variant has a 1.5L turbocharged I4 capable of achieving a combined 32 miles per gallon –– a big increase in fuel economy over its predecessor. Also in the 10th generation Gifts version, the Civic Type-R tire patches graced American soil for the first time with a 2.0L I4 with a turbo pumping out 308 horsepower and achieving a combined performance of 25 miles per gallon.
The Honda Civic has come a long way since its CVCC engine. During the 1970s, Honda adopted the slogan “We make it simpler” as a simple approach to stylish solutions. It was shown in their history and it is shown in their current products, including the Civic.
Honda continues to keep things simple and prove its place at the automakers’ table. The Civic’s radical redesign over the years wasn’t just marketing games, it was backed by engine technology that keeps it among the leaders in fuel economy, style, and recognition.
We’re excited to see where Honda takes the Civic next and we’ll be here to see how it compares to the lineup of previous Civics.
Photos: Honda
