For decades, Automobili Lamborghini has built its reputation on creating supercars with large-displacement engines. Mid-mounted naturally aspirated V12 combustion engines have been its signature since the debut of the classically stunning Miura in 1966.
But change is on the horizon, and Lamborghini’s rivals at Ferrari and McLaren have already begun the shift toward turbocharged smaller-displacement engines to maximize efficiency. Characteristically, Lamborghini is plotting a different course. Battery-electric Lamborghinis are on the CAD screens of the company’s engineers, but before they debut, Lamborghini aims to give its naturally aspirated V12 models a fitting send-off with a hybrid-electric assist.
The Revuelto is that V12 tribute model. As is customary, the car’s name comes from a traditional Spanish fighting bull. Revuelto was famous in 1880, so you’re forgiven if you haven’t heard of him. The word means “mixed up,” and it was chosen in reference to the Revuelto’s combination of combustion and electric power. The bull was said to be mixed up because eight different times he leapt out of the ring into the crowd in the stands.
The Revuelto is a plug-in hybrid-electric vehicle
In a step toward the electric future, Lamborghini has for the first time ever added a plug-in hybrid drivetrain that boosts efficiency and, crucially, lets the Revuelto drive into the fashionable city centers of Europe, where there are often prohibitions on combustion power. This is only the first from Lamborghini, which will electrify its entire portfolio in coming years, states chairman and CEO Stephan Winkelmann during my visit to Lamborghini’s Sant’Agata Bolognese, Italy headquarters to view the Revuelto.
“The Miura and Countach established the V12 engine as an icon of Lamborghini,” notes Winkelmann.
“However, things change and we have new challenges in front of us right here and right now,” he continues. “Geopolitics are a constant companion to all of our planning.”
The company will roll out a hybrid-electric Huracan by the end of 2024, with the first battery-electric cars arriving in 2028 or 2029. Considering the likely finite lifespan of the Revuelto, one might expect that Lamborghini would make the vehicle simply an evolutionary development, but instead they went the extra mile with a full redesign.
The Revuelto features an all-new carbon fiber platform, an all-new combustion engine, an all-new transmission, and even a new drivetrain layout in the chassis. The chassis is 10 percent lighter and 25 percent stiffer than before, and employs a new carbon fiber front impact structure in place of the Aventador’s aluminum structure.
The Revuelto’s V12 engine, explained
The new 814-horsepower, 6.5-liter, L545 V12 engine still rides behind the cockpit, nestled in an all-aluminum rear subframe that is where the rear suspension attaches. At a time when rivals’ engines are muted by turbochargers, you’ll hear the Revuelto’s song better than ever, because the L545 now spins to a 9,500-rpm rev limit and explodes each combustion stroke with the force of a 12.6:1 compression ratio rather than the Aventador’s 11.8:1 ratio.
This 12-cylinder beast is even 37 pounds lighter than the Aventador’s power plant. As the Revuelto contains the last Lamborghini V12, we can chart the progress from the original engine in the Miura, which displaced 3.5 liters, spun to 6,500 rpm and churned out 280 horsepower under the more optimistic rating system of that era.
The Miura’s V12 rode side saddle, bolted transversely across the back of the cockpit, with its transaxle behind it. Its replacement, the Countach, rotated the V12 90 degrees into a longitudinal position and routed power to a transmission installed ahead of the engine. This “Longitudinale Posteriore” location was the source of the Countach’s LP500 designation, and the layout has remained that way ever since.
Until now. The Revuelto’s 8-speed dual-clutch paddle-shifted transmission was designed by Lamborgini’s engineers and is built by Graziano, the same company that built the Aventador’s transmission and also supplies them to McLaren for that company’s sports cars like the Artura, which is also a plug-in hybrid. The Aventador’s single-clutch automated manual transmission was consistently criticized for clunky shifts, so the buttery smooth action of the new dual clutch should be a dramatic improvement, especially in urban driving.
The gearbox contains a 147.5-hp electric motor from Germany’s Mahle that boosts the power going to the road. The electric motor also serves as the V12’s starter, and provides the Revuelto’s reverse function, eliminating the need for a reverse gear in the transmission. This motor can also work as a generator, letting the combustion engine recharge the battery pack when driving in Recharge mode.
This gearbox is a transverse design, mounted behind the longitudinal engine, which provides abundant packaging benefits. But crucially for the hybrid-electric Revuelto, this location leaves the car’s center tunnel vacant, so there is space there now for the car’s 3.8-kilowatt-hour lithium-ion battery pack.
The Revuelto’s battery and electric motors
Yes, 3.8 kWh is a tiny battery. Lamborghini engineers wanted to minimize the amount of mass the battery would add to the car, and the short six miles of electric-only driving range should be enough to get the Revuelto to the trendy urban club’s valet parking line on electric power.
The Revuelto is all-wheel drive thanks to a pair of 147.5-hp electric motors under the front hood. These are Yasa axial flux motors from Britain, another similarity to the McLaren Artura, which also employs compact pancake-shaped axial-flux motors.
The V12 and trio of electric motors produce a combined 1,000 horsepower. Remember that combustion engines and electric motors produce their peak power at different speeds, so you can just add up the peak power of all the motors in a hybrid system to calculate the actual horsepower total. They combine to push the Revuelto to 60 mph in less than 2.5 seconds and to a top speed of more than 219 mph.
Revuelto’s performance also benefits from advanced aerodynamics in a body shell that incorporates extra space for improved comfort. There’s an extra inch of headroom to make it easier to operate while wearing a helmet for track driving and the added 3.3 inches of legroom is a blessing, as the front wheel wells intrude into the footwell of mid-engine cars like the Revuelto.
Despite the added size, the Revuelto optimizes the balance between drag and downforce using adaptive aerodynamics, such as a rear wing that can lie flat for less drag or stand up for traction-boosting downforce. The transverse transmission leaves more space under the car’s rear, so the diffuser ramps upward at a steeper angle, contributing to the 74 percent increase in rear downforce.
At the front, downforce is increased by 33 percent thanks to a complex front splitter. That’s the chin jutting out from beneath the front bumper, and on the Revuelto it has a radial leading edge in the center between the headlights and slanted outer edges that provide downforce and create vortices (like the ones you might see off airplane wing tips in humid air) to push airflow away from the drag-inducing front tires.
The engine is exposed (kind of)
Revuelto’s coolest styling detail is its exposed engine. While typical cars have their engines covered with sheet metal hoods, and exhibitionist supercars have recently showcased their power plants beneath glass covers, the Revuelto’s combustion V12 is on proud display through an opening in the engine cover. At least, it appears to be. That’s because the engine wears a plastic cover that looks like a crinkle-finish intake plenum, so that is what is actually visible from outside the car.
The engine’s exhaust note is authentic, even if the engine itself is wearing a mask. Since this is the final V12, and to draw a contrast with turbocharged rivals with fewer cylinders, Lamborghini engineers prioritized Revuelto’s sound, says chief technical officer Rouven Mohr. “It is not only about the numbers,” he says, referring to the car’s impressive performance. “It is also about the heart. The sound. And the Revuelto is the best-sounding Lamborghini ever.”
Engineers specifically targeted the sharp frequencies in the engine’s exhaust note to cultivate a mellower bellow, he explains. And in an unprecedented Lamborghini capability, the car’s six miles of pure electric driving range means that you can also drive completely silently when exiting your neighborhood in the morning. Your neighbors will surely think this combination of roar and snore is the best kind of “mixed up” at 6 am.
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