Special Report

Ward’s 10 Best Engines

With tougher fuel-economy and emissions regulations looming worldwide, it would seem like chopping engine displacement and cylinder counts would be easy decisions for auto makers.

In corporate board rooms, that may be true. But at the product development level, engineers and designers charged with executing these orders are forced to sweat every detail.

Creating a V-6 worthy of replacing Audi AG’s superb 4.2L V-8 represents an especially tough challenge.

That’s because consumers say they want better fuel economy, but performance-car buyers are notoriously fickle. They like to talk about efficiency, but if it results in a tad less low-end torque or an exhaust note that lacks gusto, many walk away.

And that’s why Audi’s 3.0L V-6 makes it onto Ward’s 10 Best Engines list for the second year in a row.

It looks good on paper, and also delivers when the rubber hits the road. The 6-cyl. provides massive low- and mid-range torque and breathtaking acceleration. And throughout the entire power band it makes wondrous sounds.

“Really, really enjoyed this car ,” says WardsAuto.com Associate Editor Bryon Pope.

No one was caught pining for the V-6’s predecessor, even though the S4 V-8 was a staff favorite, making the list three years in a row from 2004 to 2006. True, the old V-8’s induction and exhaust sounds were a feast for the ears, but fuel economy of 15/21 mpg (15.7-11.2 L/100 km) city/highway finally wore out our irrational exuberance.

With a 6-speed manual, the all-wheel-drive S4 now is rated at 18/27 mpg (13-8.7 L/100 km). Its 333 hp is less than the V-8’s 340 hp, but the V-6 produces 23 lb.-ft. (31 Nm) more torque than its predecessor and allows the car to sprint to 60 mph (97 km/h) in 4.9 seconds, 0.4 seconds faster than the V-8.

Most importantly, the V-6 has a fatter torque curve than the V-8, which gives it better all-around drivability.

“It shows you don’t have to pay a performance penalty when you downsize,” says WardsAuto.com Editorial Director David Zoia.

The 3.0L TFSI accomplishes these feats with gasoline direct injection, called FSI, a compact Eaton Corp. Roots-type supercharger that fits neatly into the 90-degree “V” of the cylinder banks and a relatively high compression ratio of 10.5:1.

Two aluminum water-to-air intercoolers, extensive sound damping and dozens of other technical features all make this a standout V-6 that promises to seriously challenge the need for future premium V-8s.

dwinter@wardsauto.com

Ward's 10 Best Engines is a copyright of Penton Media Inc. Commercial references to the program and/or awards are prohibited without prior permission of Ward's Automotive Group.