By Justin Pritchard
You don’t need a hybrid or electric car to save fuel, thanks to advancements in power train technology that are making today’s gasoline engines more efficient than ever. Want more performance, better mileage and reduced emissions from your next ride? Any combination of the features listed below will help.
Feature: Variable Valve Timing (VVT)
Available brands: Toyota, Mazda, Chevrolet, Honda, others
The Nuts and Bolts: An engine’s valve timing controls how it breathes. Think of a cyclist pedaling up a steep hill. Breathing increases with his workload, helping his body burn more fuel to make more power. Later on, when he’s at home watching television, breathing slows as less fuel is required.
Similarly, a high performance car has valve timing set up to maximize breathing and power output, while an economy car is optimized for reduced performance and increased mileage.
For many years, having both characteristics in the same engine was impossible, but many new models employ some form of (VVT) system to offer the best of both worlds.
By monitoring driver intentions and engine operation, a variable timing system can instantly adjust engine breathing to match current conditions and demands. With VVT, engine operation is automatically altered to deliver power on an “as needed” basis.
Performance is enhanced when it’s required, and fuel mileage is maximized when it’s not.
The Gist: Drivers get improved mileage and performance with no compromise between the two. Fuel savings depends on the driver’s right foot. Look for VVT under various brand names like VTEC, VarioCam, VVT-I and VVEL.
Feature: Direct Injection (DI)
Available brands: Mazda, Ford, Volkswagen, Cadillac, BMW, others
The Nuts and Bolts: Direct injection sprays fuel straight into the combustion chamber under very high pressure. This enables precise control over fuel measurement and delivery, and results in a more complete combustion process.
The high pressure fuel also generates a cooling effect as it expands within the cylinder. This lowers combustion chamber temperatures and enables the engine to safely run leaner. Direct injection is very effective, and it’s quickly being adopted by numerous automakers.
The Gist: Originally from the world of diesel engines, direct injection is noted worldwide for its ability to reduce fuel consumption and kick up performance.
Feature: Six-speed automatic transmission
Available brands: Toyota, Ford, Mazda, Chevrolet, Volvo, others
The Nuts and Bolts: The more gears the merrier! Six-speed automatics are the new standard in transmissions when it comes to optimized fuel efficiency and performance. Compared to a conventional four-speed unit, this type of gearbox offers smoother shifting, better passing power and lower cruising revs.
More gears means more options when it’s time to downshift for a hill or to merge, too. As a result, the engine can spend less time at higher revs, reducing fuel consumption.
Additional gears also mean there’s less of a step between each one. In certain situations, this allows the engine to spend more time in its “power band” when quick acceleration is requested.
The Gist: Increased smoothness, refinement, mileage and performance. Sounds like a win-win situation!
Feature: Turbocharging
Available brands: Ford, Acura, Volkswagen, Mitsubishi, Saab, others
The Nuts and Bolts: A turbocharger effectively transforms a smaller engine into a much bigger one by feeding it compressed air and extra fuel. Unlike a larger powerplant, a smaller turbocharged engine only delivers extra power when it’s required. Put another way, drivers only pay the fuel penalty on the power they use, rather than feeding a bigger engine all the time.
The Gist: Keep your right foot in check, and you’ll get small-engine fuel bills with big-engine power at the ready.
Feature: Dual-clutch Transmission
Available brands: Audi, Porsche, Mitsubishi, Ford, Volkswagen, others
The Nuts and Bolts: This special type of transmission acts as two manual gearboxes operating in parallel—with a separate clutch for each one. Gears shift smoothly and instantly, with no interruption or pause in power delivery.
Many dual-clutch gearboxes also include paddle shifters mounted to the steering wheel. This takes advantage of their sporty operation and lightning-fast gear changes.
In addition to fully automatic operation, the dual-clutch transmission offers the same performance and fuel mileage benefits as a regular manual. Typically, they’re more efficient than an automatic, too, meaning more engine power makes its way to the road.
Since many dual-clutch or direct shift transmissions have no fluid, pump, cooling requirements or torque converter, they’re lighter than an automatic, too.
The Gist: More fun, better mileage, no compromise.
