1) 3.0L Turbodiesel DOHC I-6 (BMW 535d)
It could be argued that 2013 was the year of the diesel, as more automakers offered the low-reving oil-burners this year. Savvy automakers like BMW used the fuel to juice up their model lineups with better fuel efficiency, without ruining the fun factor. The 3.0-liter turbodiesel found in the 535d as well as the X5 uses a single turbocharger to deliver peak torque of 413 lb-ft as soon as 1,500 rpm. Without a doubt, BMW’s diesel delivers the twist, but also manages to be fuel friendly and quiet, hence it’s place on this top 10. [Read: Weirdest Gadgets Ever Invented]
2) Audi: Supercharged 3.0-liter V-6
Audi's 3.0-liter, supercharged V-6 engine makes the list 7 bet car engines of 2014. Characterizing the engine as possessing "brute strength, luscious torque, and supreme refinement,"
3) Honda’s 3.5 liter V6 (Accord)
“This unflappable V6 is the best naturally aspirated [six cylinder] engine in a mainstream vehicle at a time when most automakers are switching instead to turbocharged direct-injected [four-cylinder] powerplants for better fuel efficiency,” Honda’s 3.5 liter unit has been a favorite of the judges for a number of years.
4) Fiat 500e 83-kw electric motor
This car earned a spot on the list scoring big points. This zero emissions electric motor has an estimated range of 85 miles running solely on electric power. The motor packs a punch, using 100 percent of its 147 lb-ft of torque off the line.
5) 1.8L Turbocharged DOHC I-4 (Volkswagen Jetta)
The 1.8-liter four-cylinder engine that’s packed under the hood of the compact Jetta sedan is the latest generation of Volkswagen’s renowned turbo-four, and it remains one of the best in the business with lively acceleration and good fuel economy, realizing close to 30 mpg in mixed driving. According to the publication, “there are several excellent four-cylinder turbocharged engines in the U.S. market, but VW's re-engineered 1.8-liter represents the new benchmark.”
6) 5L SOHC V-6 (Honda Accord)
Powerful and surprisingly economical 3.5-liter V6 that’s available in the midsize Accord. Coming with automatic cylinder deactivation, the V6 beats many smaller engines in terms of fuel economy with an EPA-rated 34 mpg in highway driving.
7) 2.7-liter DOHC H-6 boxer (Porsche Cayman)
The Porsche 2.7 liter flat-6 just continues to rack up awards despite being the smallest and least powerful engine Porsche offers. Why? Because it is incredibly efficient. This motor won an International Engine of the Year award earlier in the year The 2.7 liter motor puts out 265 horsepower in the Boxster and 275 horsepower in the Cayman. That means over 100 horsepower per liter yet is capable of 34.4 MPG on the combined cycle.
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