When Volvo Car Corp. said it added a little “naughtiness” to its new ’11 S60 sport sedan, we had our doubts.

After all, this bold claim was coming from an auto maker long known for its bulletproof safety and staid designs. Yes, the sheetmetal definitely is sexier, naughty even, but we were more interested in what was under the hood.

Boy, were we surprised. The S60’s 300-hp 3.0L DOHC inline 6-cyl. turbocharged “T6” engine provides maximum torque of 325 lb.-ft. (440 Nm) from 2,100 rpm to 4,200 rpm. Good figures on paper, but even better on the road.

While some judges wanted a little more low-end torque, most were pleased, especially with the complete absence of turbo lag.

“No turbo lag, even when dramatically slowing and then aggressively accelerating,” says Judge Christie Schweinsberg.

Under hard acceleration, there is little complaining from the T6, which seems to enjoy it.

The exhaust note, although somewhat subdued, is more aggressive than that of Volvos past and imbues the S60 with a certain degree of sportiness.

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Even while driven vigorously, the S60 gets decent fuel economy, with judges achieving 22.4 mpg (10.5 L/100 km) on average in combined highway and city driving.

Equally impressive is the fact the T6 is based on a 20-year-old architecture. The aluminum block may be the same, but the latest iteration receives numerous modifications, including new friction-reduction materials, “super-ignition” sparkplugs and an oil-scraping plate that prevents oil from following the rotating crankshaft and causing turbulence.

Volvo engineers also extensively reworked the T6’s mapping software and fine-tuned the twin-scroll turbocharger to spread torque evenly through the power band.

From the onset of the S60 program, Volvo’s intent was to create a sport sedan that could compete with the best Germany has to offer, and the auto maker delivers, in spades.

The S60 is the perfect fit for this engine and makes Volvo a serious contender in the luxury sport sedan segment.

bpope@wardsauto.com

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