THE REVUELTO IS NAMED FOR A SPANISH bull with a rebellious streak, but this new Lamborghini is more than rebellious-it's revolutionary. Its closest sibling is the Aventador it replaces because they both have a V-12 engine, but the similarity begins and ends there.

With no turbochargers, the sound of the mighty 6.5-liter V-12 is as glorious as ever. Much of it breathes better, from the reworked air intake to a compression ratio that's been jacked up from 11.8:1 to 12.6:1 and finally to an exhaust that flows better at high revs. How high are those revs? The redline is now a mind-boggling 9400 rpm, and peak output is 814 horsepower at a scorching 9250 rpm, some 45 horses and 750 revs more than the exiting Aventador Ultimae. Oh, and the engine sheds a claimed 37 pounds in the bargain.

Moreover, engineers stripped the V-12 of its forward-mounted transmission (the often maligned and always jarring seven-speed automated manual), spun it around 180 degrees, and mated it to a new eight-speed dual-clutch transaxle made by Lamborghini. Placed behind the engine as God intended, this new gearbox is only 22 inches long because it is laid out laterally around two input shafts-one for the even-numbered gears and another for the odd ones-and sits parallel to the half-shaft output flanges. Unlike in its predecessor, shifting is smooth whether you are puttering around town, hammering it in the hills, or making a quarter-mile pass. As with the best dual-clutch automatics, it's near impossible to spot the shifts in a speed trace.

The Revuelto has all-wheel drive like the Aventador, although it's provided by electric motors, not any connection to the V-12. Instead of a transmission tucked between the front seats, there's a 3.4-kWh battery pack. A 147-hp, 110-lb-ft motor buried within the transmission housing can drive the rear wheels when the conditions are right and, along with regenerative energy under braking, keeps the battery topped up.