In hot pursuit of an F1 engine in a street car
FUTURE MODELS/ Michael Taylor takes a look at the mechanics of the new Mercedes-AMG Project One hypercar
Mercedes-AMG has finally shown the mechanical layout of its thousand horsepower, Formula 1-inspired Project One hypercar at a sneak reveal at the Nürburgring 24-hour race.
AMG chairman Tobias Moers insists the car will become the new hypercar benchmark, with power of 750kW from the F1-based 1.6l, electrified, turbocharged V6 and its four electric motors. Only 275 will be built. The all-wheel-drive hypercar won’t just deliver levels of performance unparalleled outside the world’s racetracks but will be able to run as a pure battery-electric car for up to 25km and, unique for a hypercar, its zero-emission mode will be front-wheel drive. That should make it capable of circumventing limitations on internal-combustion, highpowered cars in some city centres around the world.
“It shifts up the boundaries of what is technically feasible,” Moers says. “We are the first to make pure-bred F1 technology roadworthy. Our objective is not speed but to be the benchmark.
“If we have a strategy and we move into a new era of performance at AMG, maybe it’s good to have something that opens the door in a very authentic way to that new era and this is it.
“Plug-in hybrid is going to be the future for AMG. We get more performance and more efficiency; what’s wrong with that?”
Technically, Ferrari used an F1 engine as the basis of its F50 supercar in 1995, though Moers insists the Project One will be a class forward from the least loved of the hypercar Ferraris.
“We are talking about a highperformance hybrid, with one combustion engine and four electric motors.
“The combustion engine comes from Brixworth (the UK engine development centre for the Mercedes-AMG F1 team), from the same people who delivered three consecutive Formula One world championships for drivers and manufacturers.
HI-TECH TURBO
“The redline is at 11,000 and it has a hi-tech turbo, which is driven by an 80kW electric motor. Its batteries are the same technology and arrangement as in F1, but we will build four times the storage, with about 25km of pure electric range.
“We have reached thermal efficiency of 43%. Nobody else has managed anything like that, street legal.”
By comparison, AMG’s 4.0l biturbo V8 has a thermal efficiency of about 25%.
At $2.54m, the two-seat, hard-top coupe follows F1 practice by basing the entire car around a carbon fibre chassis tub, then mounting the engine directly to the tub and mounting the gearbox and differential unit directly to the engine.
The engine and eight-speed gearbox will be fully stressed parts of the chassis layout, while AMG has chosen to use a computer-controlled clutch on a traditional manual gearbox, rather than the dual-clutch transmission layout most supercar makers, including Bugatti, favour.
The first deliveries of the car are due late in 2018, with Moers hoping to finish the production run by the end of 2020. AMG already has one mule prototype running to help with initial verification of the powertrain and chassis concept.
The key part of the technology is the Project One’s powertrain, which it insists it pulled directly from its F1 programme. Though heavily revised from the W08 EQ Power+ F1 car used by Lewis Hamilton and Valtteri Bottas in Monaco, Moers insists the modifications are only basic.
“The idle speed is 1,100r/min and in F1 it’s 3,800 or 4,000. It revs to 11,000r/min, but in F1 it’s 13,500.
“We have to move combustion ratio … that’s what changes. In F1 they run Lambda that’s way more than one. But we can’t because of emissions.
“We have the same cylinder head, same crank housing but a different crankshaft.”
For all that, Moers insists customers won’t need the usual array of F1 race engineers and laptop computers to start the engine. “It will be a street car. You keep it plugged in in the garage. You fill it with 98 [fuel].”
The trickier parts of the powertrain will be the way it combines its electrified and internal-combustion power. A ground-breaking engine in F1, the AMG V6 splits its single, large turbocharger, with the exhaust turbine moved to the back of the engine with the exhaust system and the compressor wheel sitting at the front of the engine where the cooler air is, and a shaft running through the engine’s vee angle to join them together.
First, there is the power and torque from the tiny 1.6 V6 (which AMG wouldn’t talk about, but which must be somewhere around 350kW). Then it also has a 100kW electric motor (the MGU-K for “kinetic” in AMG-speak) directly attached to the engine’s crankshaft and another 80kW (the MGU-H for “heat”) electric motor that spins up the turbocharger to eliminate turbo lag. Then there is a 120kW electric motor for each front wheel, which uses essentially the same construction and design as the MGU-K, but in different housings.
While Moers would not be drawn on the car’s target weight, he did confirm that the entire powertrain would weigh about 420kg, with the battery pack accounting for 100kg of that.
The battery, built by its F1 supplier, ABC, runs the same chemistry, cells and connectors as Hamilton’s racer but is four times larger to add in the Project One’s zero-emission capability.
What makes it particularly complicated is that all its electric motors act as both motors and generators to recharge the fastdischarge battery, which has a 800V-12V converter sitting on top of its housing.
The extreme forces acting inside the highly stressed 1.6 V6 mean AMG will only rate it for 50,000km before it needs to be “remanufactured”.
“We have an understanding of about 50,000km. This is okay for us. I think that’s good enough,” Moers insists.
“That’s the life of the engine. Then we do some rework, like in a race car.”
After 50,000km, the engines would either be rebuilt by AMG or, depending on the work needed, replaced. AMG didn’t rule out customers choosing to buy the car with a spare engine ready to go. As an aside, it has yet to put a price tag on either a new engine or a rebuild.
DISBELIEF
The supercar industry’s widespread reaction to Moers’s claims of using a Formula One motor has been disbelief.
Ferrari basically said it did not believe Mercedes-AMG. Ferrari, the only other racewinning F1 engine supplier in 2017, clearly doubts whether AMG’s hypercar uses an F1sourced engine — and whether that would be a good idea in the first place.
In an interview at the Geneva motor show, Ferrari’s road-car chief engineer, Michael Leiters, said there was no way Ferrari would follow suit.
“Putting an F1 engine into a road car? We already did it with the F50 and I’m not convinced it works. An F1 engine runs at 16,000rpm. How can you use a car that revs to 16,000rpm on the street?
“You can’t, and if it doesn’t rev to 16,000rpm, you have to ask the question: what remains of the Formula 1 engine?”
With development ongoing, it will be fascinating to see how the Project One emerges as a finished project.