Ferrari’s First V6 Placed in Hybrid Hypercar

Paul Myles

TU-Editor

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25th June 2021

Ferrari has unveiled its first V6 powered road-going sportscar in the shape of the plug-in hybrid 296 GTB.

It’s the latest evolution of Maranello’s mid-rear-engined two-seater Berlinetta able to handle both sports focused driving and day-to-day commuting work. Joining the marque’s usual V8 and V12 motors, the 650bhp 120° V6 is coupled with an electric motor capable of delivering a further 160bhp. That combination allows the car to claim a 0-62mph sprint time of 2.9 seconds on the way to a top speed of more than 205mph. More importantly, it fastest lap time of Ferrari’s Fiorano test track is 1 minute 21 seconds just over a second slower than the road car track record held by its bigger sibling hybrid, LaFerrari.

The engine draws on Ferrari’s extensive Formula One experience using V6 hybrid powertrains in its racing cars since their introduction to the series in 2014. Its hybrid system employs ICE with a 120° vee architecture, offering more space between the cylinder banks than a 90° vee and allowing the turbos could be installed centrally, so reducing the unit’s overall size and the distance the air has to cover to arrive in the combustion chamber, boosting the fluid dynamics and efficiency of the intake and exhaust line ducts.

The engine benefited from the latest Ferrari combustion chamber development introduced on the SF90 Stradale with central injectors and spark plugs with 350-bar pressure injection system that improves the fuel-air mix in the chamber, performance and reduces emissions. The IHI turbochargers have been redesigned using higher performance alloys. This meant the maximum revs of the turbos could be increased to 180,000 rpm, with a consequent improvement in performance and boost efficiency, which increases by 24%. The symmetrical, couter-rotating turbos are of the mono-scroll type: the technical solutions adopted have reduced the compressor wheel diameter by 5% and the turbo rotor 11% compared to the V8 applications, despite the high specific power. The reduction in the rotating masses (the inertia of the two rotating elements has been reduced by 11% compared to the 3.9l V8 solution) has reduced the spool up time ensuring fast power delivery.

The crankshaft is made from nitrided steel. To ensure it has a 120° crank angle, after the initial forging of the rough ingot, the crankshaft is twisted and then subject to a deep nitriding heat treatments, machining and balancing. The firing order of the new V6 (1-6-3-4-2-5) is the result of the crankshaft’s journal geometry. Ferrari claims 100% of the rotating masses and 25% of the alternating masses are balanced and, therefore, its level of balance allows loads on the bushings to be reduced without increasing the weight of the engine.

In Ferrari engines, the intake plenum is normally located in the center of the vee. However, the V6 has its plenums are on the side of the cylinder heads and are integrated with the support for the throttle valve. The light thermoplastic material used to make them keeps engine weight down. This solution boosts performance because of the shorter ducts and consequent fluid-dynamic detuning, in addition to reducing time-to-boost as a result of the high-pressure line’s smaller volume.

On the hybrid side of the powertrain, its boats a rear-mounted electric motor derived from the F1 application from which it also inherits the MGU-K (Motor Generator Unit, Kinetic) moniker. The electric motor and ICE communicate via the Transition Manager Actuator (TMA) which allows them to be used both together or decoupled to allow the electric motor to run solo for a range of 15 miles.

The MGU-K is a dual-rotor single-stator axial flux motor. Its compact size and its structure allowed the length of the powertrain to be reduced which helped shorten the 296 GTB’s wheelbase. The electric motor charges the high voltage battery, turns on the ICE, supplies it with additional torque and power and allows the car to be driven in all-electric eDrive mode. The MGU-K’s improved design allows it to reach maximum torque of 232ft-lbs, around 20% more than previous applications.

Thanks to the use of laser welding in its construction, the 296 GTB’s high voltage battery has a 7.45 kWh capacity and a competitive weight/power ratio. The battery pack is located under the floor and to reduce volume and weight, the cooling system, structure and fixing points are integrated into a single component. The cell modules contain 80 cells connected in series. Each Cell Supervisor Controller is installed directly in the modules to reduce volume and weight.

— Paul Myles is a seasoned automotive journalist based in Europe. Follow him on Twitter @Paulmyles_