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Enduring Internal Combustion

by Todd KahoJuly 4, 2019
Many consider the internal combustion engine a thing of the past. After all, we have zero-emission electric cars and a growing number of hybrids. But conventional engines keep getting better and will power most cars and trucks for some time.

Internal combustion engines power the vast majority of the cars and trucks on the road today. That’s not by any means a bad thing. While electrification of our cars dominates most of today’s headlines and resources, the internal combustion engine is still what moves most of us from one place to another.

These tried-and-true powerplants have evolved to meet modern requirements in ways that lend flexibility to current and future needs. A primary advantage to internal combustion is that engines can be powered by multiple fuel sources including gasoline, diesel, and an array of alternative fuels. That flexibility provides options moving forward.

Hybrid cars and trucks, in all their configurations, are a gateway to pure electric vehicle acceptance. Gasoline-electric hybrids rely on an efficient internal combustion engine to function. The hybrid envelope has expanded in recent times to include plugin models that can travel varying distances on pure electric power as well.

Automatic start-stop function is an important technology that makes internal combustion vehicles more city-friendly by shutting an engine off when stopped at a traffic light for more than a few seconds, eliminating unnecessary idling emissions. The engine remains off as long as a driver’s foot is on the brake pedal and the vehicle is not in motion. When the light changes, lifting off the brake immediately restarts the engine and you drive away.

Fuel economy improvements, lower carbon emissions, and overall emissions reductions are also being accomplished by other strategies. Among the most prominent is engine downsizing, which allows the use of smaller displacement engines boosted with power-adding technologies like turbocharging. The old adage, ‘there’s no replacement for displacement,’ is being successfully circumvented by smart engine downsizing.

Some elegant solutions are presenting themselves. One example is Nissan’s VC-Turbo, the world’s first variable compression production engine. Modifying engine compression ratio through sophisticated computer control allows adjusting compression in real time, optimizing efficiency and performance depending on driving conditions.

Another example is the introduction of Chevrolet’s next-generation Dynamic Fuel Management in Silverado 5.3-liter and 6.2-liter V-8 engines. This advanced technology optimizes power and fuel efficiency through cylinder deactivation, determining 80 times-per-second how many cylinders are actually needed for real-time driving needs, with the engine running on as little as a single cylinder to save fuel and decrease carbon emissions.

Gasoline engines have traditionally required a spark plug to ignite the fuel-air mixture in an engine’s combustion chamber to drive a piston. More thermally efficient diesel engines create ignition as a piston compresses the fuel-air mixture at high pressure, without a plug. So, what if you could combine the best of both worlds and make a gasoline engine work more like an efficient diesel? 

It now appears the technology is ready for prime time and production. Mazda’s new SKYACTIV-X is set to become the world’s first production engine to use compression ignition in a commercially available gasoline engine. The automaker’s proprietary Spark Controlled Compression Ignition design provides considerable torque during acceleration, along with sharp engine response, improved fuel efficiency, and lower emissions. 

The worldwide push toward electric vehicles has yielded some surprising consequences. One is an all-out effort to make combustion vehicles better and more competitive with the advancement and sharing of technologies across all platforms.

Is the internal combustion engine dead? Hardly. It just keeps getting better, more efficient, and technologically advanced as the years roll by.