Like the Coupe, the Aventador Roadster is underpinned by a carbon-fiber chassis that teams with a number of other carbon and aluminum components throughout the car to keep weight down. Despite additional structural bracing to compensate for the lack of a fixed top, the Aventador gains just 110 pounds in the transition from Coupe to Roadster - although few would call the 4200-pound curb weight dainty.
Concerns about weight - and most other rational thoughts - are extinguished once one experiences the Aventador Roadster's mellifluous and absurdly potent V12. Displacing 6.5 liters and boasting a lofty 8500 redline, this beast of a motor makes 691 horsepower and 509 lb-ft of torque at 5,500 rpm.
When you couple that much power with the car's Haldex all-wheel-drive system, what you get is a zero-to-62 mph time of just 3.0 seconds and a top speed of 217 mph. These figures put the Aventador Roadster proudly atop the Lamborghini's convertible range and easily in the company of the most impressive drop-topsupercars in the world.
Fuel economy is likely the last thing on the mind of anyone considering a Lamborghini, but the automaker added two new technologies to the coupe - which also debut on the roadster - for the latest model year in the interests of efficiency and the environment.
The first, a start-stop system that shuts down the engine to save fuel at traffic lights or in stop-and-go traffic, is a supercapacitor-based system that's both lighter and faster to restart the motor than a traditional battery-based system. The second is a cylinder deactivation system that shuts down half of the V12's cylinders during light-throttle situations, temporarily turning the motor into a straight-six. When the driver lays into the throttle, the other six cylinders fire back up for full power.
Despite those technologies, there's only so much they can do to enhance the mileage of the inherently thirsty V12 - fuel economy is rated at 10 mpg in the city and 16 mpg on the highway.
Shifting duties are handled by a seven-speed single-clutch automated manual gearbox that Lamborghini refers to as a robotized Independent Shifting Rods (ISR) transmission. Capable of blasting from gear to gear in just 50 milliseconds, it can be a bit herky-jerky at low speeds and isn't as refined overall as the dual-clutch boxes used by some competitors. Lamborghini said it opted to use the ISR to save weight over a dual-clutch unit.
Helping transfer all 691 horsepower to the ground at all four corners are two different tires and wheel sizes - 255/35/R20 for front wheels and tires, with massive 335/30R21 wheels and tires for the rear. Stopping the big Lambo are 400x38m six-piston carbon ceramic brakes in the front, and 380x38mm carbon ceramic brakes in the rear.
Get the Aventador Roadster out to an empty, winding road, and the supercar will impress with its superb engine, accurate steering and excellent overall balance, though its girth prevents it from feeling truly nimble. Technically, the roadster's torsional stiffness with its roof removed is 37-percent lower than that of the coupe, but most drivers will be hard-pressed to notice the difference on the road.
Clip the two-piece targa roof - a simple process of placing the top's locating pins into four windshield sockets and securing two rear latches - into place, and the roadster gains an additional 10 percent of torsional rigidity. When removed, the top can be stored in the front trunk, where it eats up nearly all of the already limited cargo space.
The roadster features two pop-up b-pillar posts to protect occupant's noggins in the case of a rollover, in addition to a model-specific rear window that can be lowered for optimal access to the V12 soundtrack.
Standard tech is in
Standard features are quite extensive, including electronic control goodies such as ABS, EBD, ASR, ESC, a hill holder function, an electronically controlled rear spoiler, an electronically controlled side air intake system, servotronic and an integrated command with three different driving modes that integrate the gearbox, differential, engine response and servotronic simultaneously.
Interior and vehicle standard features include: Push to Start/Stop button, keyless ignition, full TFT displays in the cockpit, on-board computer, multimedia system with seven-inch display, iPod and USB interface, navigation, Bluetooth, bi-xenon headlights with washer, LED daytime running lights, automatic air conditioning with solar sensor, crepuscular and rain sensors and electrically adjustable and heated side mirrors with folding function.
The Aventador Roadster also uses pushrod suspension technology, inspired by Formula 1 racing. It functions by locating the springs and dampers not on wheel mounts, but rather inboard to the body shell. The end result when coupled with the double wishbone suspension is precise handling in dynamic driving conditions, but almost luxury-like comfort when cruising.