HOMESTEAD, Fla. — Heat waves ripple off black asphalt in Pit Lane at Homestead-Miami Speedway spread across swampy Florida marshes, where the high-revving engine of a sleek SLK350 two-seat sports car from Mercedes-Benz of Germany purrs at idle as a driver straps into the contoured driver’s bucket for some hot laps on Homestead’s spaghetti-wiggly 2.1825-mile infield road course.

The new styling for this car looks hot too.

It hunkers low on big alloy wheels capped by speed-rated 225/40R18 (front) and 245/35R18 (rear) low-profile tires below a sleek package that suggests swift movement even when parked in the pits.

An aggressive prow on the SLK350 — a design homage to the Mercedes-Benz SLS AMG supercar — focuses on a large grille studded with the tri-star Mercedes emblem and flanked by a horizontal bar and optional adaptive bi-xenon headlamps posted on the front corners.

Body lines are classic for a roadster with a long front hood that sweeps up the steep rake of a windscreen and over the two-seat cockpit to a brief boot in back.

But there’s more:  Mercedes takes the concept of a breezy ragtop roadster one step beyond the expected by adding a hardtop that folds origami-fashion and tucks away in the trunk. The transformation from a weather-tight hardtop coupe to airy convertible is a high-tech mechanical operation accomplished in only 20 seconds.

For the 2012 SLK350, Mercedes offers three versions of the folding hardtop roof:  There’s the conventional body-color roof panel, a panorama roof panel composed of tinted polycarbonate, or a new Magic Sky Control glass roof panel containing a film with chargeable particles which vary the tint from light to dark at the press of a button.

The 2012 SLK350 represents a new generational design built on a new platform. The car measures 1.5 inches wider, 1.5 inches longer and 0.5 inches lower than last year’s model.

Independent suspension elements are tuned for tight control and sporty traits.

Components include MacPherson struts up front with two-piece lower control arms and coil springs, while at the rear there’s a multi-link arrangement with anti-lift and anti-squat geometry plus single-tube gas-pressurized shocks.

Steering mechanism is a direct and responsive rack and pinion system.

The SLK350 also stocks an array of computerized electronic hardware for vehicle control and safety.

There are devices aboard to stabilize forward movement and tire traction, rollover sensors to gird for an impending accident, plus smart brakes with anti-lock (ABS) and brake assist (BAS) systems.

With the electronic stability program (ESP), sensors measure wheel speed and lateral acceleration and can brake an individual wheel to correct potential skidding or spinning of the car.

Also, the SLK350 carries multiple air bags to cushion the human cargo including seat-mounted air bags for shielding head and thorax regions of riders in the two seats, even air bags to protect the knees.

Nomenclature for SLK conforms to the alphanumeric designations employed by Mercedes for all of its vehicles, with the class size defined by alphabetical letters and the engine volume expressed in liters and translated to digits.

Thus, SLK350 takes its name from the SLK Class of convertible roadsters and a 3.5-liter V6 engine with engine displacement turning into the numbers 350.

Likewise apply the name for a soon-to-arrive 2012 SLK55 AMG and its hand-built 5.5-liter V8 from AMG, the Mercedes performance-tuner collaborator.

For the 2012 SLK350, the Mercedes 3.5-liter V6 — with aluminum block and heads, dual overhead cams plus direct injection — produces 302 hp at 6500 rpm and a flat line of torque that reaches to 273 lb-ft between 3500 and 5250 rpm.

To manage the torque, SLK350 brings a sporty seven-speed automatic with shift paddles on the steering wheel and a TouchShift console stick for manual shift control.

Mercedes track tests indicate the 2012 SLK350 will zip to 60 mph in 5.4 seconds. Fuel economy estimates for the V6 engine tally to 20 mpg (city) and 29 mpg (highway).

A new design for the SLK cabin features a cockpit with twin bolstered bucket seats separated by a console.

A load of premium standard equipment ranges from fine leather upholstery to eight-way power controls for seats with four-way lumbar support, a single-zone analog climate control system with max cool function, three-spoke leather sport steering wheel with audio controls and the shift paddles, power controls for windows and door locks, heated power folding exterior mirrors with turn signals and driver’s side auto-dimming, a remote keyless entry device and theft-deterrent system, rain-sensing intermittent wipers, mesh windscreen, electronic cruise control, 5.8-inch dash display with central controller, Harman Kardon LOGIC7 audio system with AM/FM/CDx6/MP3, plus Bluetooth audio streaming and wireless cell-phone link.

Also, the SLK350 lists many optional equipment packages:  A Multimedia Package, Premium Package, Dynamic Handling Package, Sport Package, Distronic Plus Package with Pre-Safe crash safety system, Lighting Package and a Wood Trim Package.

Mercedes sets the MSRP for a 2012 SLK350 at $54,800.

2012 MERCEDES-BENZ SLK350 COUPE AND ROADSTER SPECIFICATIONS

• Description: Sports coupe/roadster
• Model options: SLK350
• Wheelbase: 95.67 inches
• Overall length: 162.76 inches
• Engine size: DOHC 3.5-L V6/DI
• Transmissions/speeds: Auto/7/TouchShift
• Rear/front drive: Rear
• Steering: Power rack and pinion
• Braking: Power 4-disc, ABS/BAS/ASR/ESP
• Air bags: 2 (front), 2 (side), 2 (knee)
• EPA mileage est. city/hwy.: 20/29 mpg
• MSRP, est.: $54,800