Editor’s Note: Ward’s 10 Best Engines competition has recognized outstanding powertrains for 21 years. This installment of the series analyzing last year's choices looks at the development of Volkswagen’s 1.8L gasoline-powered I-4.

Marcel Zirwes, product manager- Powertrain, VW of America, was interviewed before the automaker admitted to installing illegal emissions software in 11 million diesel vehicles worldwide.

The 1.8L TSI engine is part of VW’s EA888 family of fuel-efficient gasoline 4-cyl. engines.

WardsAuto hasn’t put a version of VW’s now infamous 2.0L diesel engine on the 10 Best Engines list since 2011. In recent years, editors believed VW's gasoline engines were better. VW is returning the diesel awards for 2009, 2010 and 2011.

Gasoline engines are not involved in VW’s current emissions cheating scandal, but we have elected not to include this engine or any other VW and Audi powertrains in the 10 Best Engines program until further notice.

The latest version of Volkswagen’s 1.8L TSI turbocharged DOHC I-4 arrived in 2012 boasting a liquid-cooled exhaust manifold integrated into its cylinder head. VW says that was a first for any turbocharged 4-cyl. engine.

Turbocharged I-4s have proliferated throughout the industry as replacements for larger displacement 4-, 5- and 6-cyl. engines, offering higher fuel efficiency and similar or better performance. Most today feature direct gasoline injection, but one characteristic that differentiates this family, known as EA888, from most others is its modularity.

“This is a big engine family, from the 1.8L turbo up to the high-power 2.0L turbo in the Golf R,” says Marcel Zirwes, product manager-Powertrain, VW of America. (Zirwes was interviewed several weeks before the VW diesel emissions scandal broke).

The engines are more costly than naturally aspirated I-4s because they all are turbocharged. “Turbocharging is a big step in technology and fuel efficiency,” Zirwes says, “but good value for the customer. And this engine is very flexible. The low version has a cost efficiency advantage over most competitors, and higher versions have more technologies. It’s a toolbox that enables us to do a lot of different things depending on the vehicle, the segment, customer expectations and what they are willing to pay.”

The base 2.0L, for example, has just two valves per cylinder, while the 1.8L Turbo has 16 valves and intake-side variable-valve timing. The GTI’s 16-valve 2.0L Turbo has VVC on intake and exhaust sides, plus variable valve lift.

This 1.8L Turbo is much more fuel efficient than the naturally aspirated 2.5L I-5 it replaced in the Golf, its emissions are much lower, and it generates 170 hp at 700 rpm lower in the power band and a strong 200 lb.-ft. (270 Nm) of torque for sub-7-second 0-60-mph (97 km/h) acceleration.

WardsAuto judges laud both its fuel efficiency and its performance – especially its surprising torque at low rpms – and its availability in affordable vehicles.

“The 1.8L is an accessible, delightful engine that can be had for under $18,000 in the Golf,” they reported after logging nearly 300 miles (483 km) in a 5-speed manual ‘15 Golf TSI. And they routinely achieved 33 mpg (7.1 L/100 km) or better, well in keeping with its 25/37 mpg (9.4-6.4 L/100 km) city/highway and 29 mpg (8.1 L/100 km) combined EPA ratings.

Compared with the award-winning 1.8L editors tested last year in a ’14 VW Jetta, the ’15 version “achieves the same peak 170 hp 300 rpm earlier, and the most noticeable improvement is an extra 16 lb.-ft. (22 Nm) of torque, said editor Christie Schweinsberg, adding that it isremarkably vibration-free.”