With its innovative electrified powertrain, Audi is looking to take on the world’s toughest off-road race – and make history once again.
It’s the engine note (or the lack of it) that hits you first. When you see a rally car barrelling towards you, you expect the whine and pop of a turbo, the seemingly never-ending blat-blat-blat of sequential upshifts, the deafening staccato of a petrol engine rattling against the rev limiter. The new Audi RS Q e-tron strikes a very different tone.
That’s because the Audi RS Q e-tron has an electrified drivetrain. It’s designed to conquer the Dakar Rally: one of motorsport’s last truly gruelling epic endurance races, and the ultimate test for Audi’s e-tron technology, as it takes on both its off-road rivals and the elements in the searing white-hot heat of competition.
Taking on motorsport’s toughest test
Driven by its ‘Vorsprung durch Technik’ ethos of ‘progress through technology’, Audi has long used motorsport as the ultimate engineering proving ground – honing quattro all-wheel drive in the World Rally Championship, hybrid power at the Le Mans 24 Hours and all-electric power in the Formula E single-seater series. Now, the same is true for its next stage of electrification, with Audi using the 2022 Dakar Rally as the ultimate proving ground for future road-going e-tron technology.
Formerly held in the North African deserts and South America’s Andes mountains, the Dakar Rally is now based in Saudi Arabia. Over two weeks an 8000km route – featuring day-long competitive stages up to 800km in length – will take teams from the city of Ha’il across the breadth of the Arabian Peninsula to Jeddah on the Red Sea coast. Along the way, the Audi RS Q e-tron will have to conquer rugged roads, rocky canyons and the towering remote desert dunes of the Rub’ al Khali (ominously known as ‘The Empty Quarter’). It’s one of racing’s toughest challenges.
“When I first heard about the idea of taking Audi to the desert, I said: ‘Wow. That’s something completely new,” recalls Audi Sport project manager Andreas Roos. “The Dakar Rally is extremely challenging, even for a conventionally powered vehicle. With our powertrain, the challenge is even greater. No regulations existed for an electric drive concept like this. What we’re trying to do has never been done before.”
Electric to its core
Bringing together engineering expertise from across Audi’s hugely successful race programmes in the Le Mans 24 Hours, the German DTM, World Rallycross and Formula E – while adding the Dakar Rally-winning expertise of Sven Quandt and his Q Motorsport team for good measure – the result is the innovative Audi RS Q e-tron.
Its pulsing heart is an innovative drivetrain that uses two electric motor generator units (or MGUs) – one on the front axle, one on the rear. Developed from the MGU05 that propelled Audi’s race-winning Formula E to victory in 2021, they’re powered directly by an advanced high-voltage 50kWh lithium-ion battery. The Audi RS Q e-tron’s motors are also linked across the chassis by a ‘virtual’ software-driven centre differential with variable torque distribution. The result: up to 300kW of quattro performance, 0-100km/h in 4.5s and a 170km/h limited top speed.
As recharging options on the Dakar Rally’s desert stages are somewhat limited, the way the Audi RS Q e-tron recharges itself mid-stage is equally clever. A third MGU05 acts as a generator, recapturing energy from the advanced ‘brake-by-wire’ system while decelerating.
Also on-board is a TFSI petrol engine – developed from the 2.0-litre four-cylinder turbo used in the Audi RS 5 raced in the DTM. Operating in a narrow ultra-efficient power band of between 4500rpm and 6000rpm to keep its efficiency high and it emissions ultra-low, it supplements the MGU to recharge the battery when needed.
“The crucial thing is that our drivetrain is fully electric,” says Andreas. “The TFSI engine – which is incredibly efficient and state of the art in terms of its weight and fuel consumption – is only used to charge the batteries on the special stages. We’re planning to run fully electric on all the liaison stages.”
Sculpted for success
The Audi RS Q e-tron’s rugged muscular form may be dictated by the challenges of off-road racing, but it’s also full of subtle Audi references. “This isn’t a concours d’elegance,” says Juan Manuel Diaz of Audi Motorsport Design. “We’re talking about racing and winning. But you can immediately tell it’s an Audi at first glance.”
The shark-like fin and large rooftop cooling vent evoke Audi’s R18 e-tron Le Mans prototypes, while the coupe profile was inspired by the road-going e-tron Sportback SUV. The protrusions behind the doors nod to the side blades of the Audi R8, but in this case contain two huge spare wheels – essential insurance for off-road rallying. The huge angular fenders hark to Audi quattro heritage, while the scratch-resistant heated laminated windshield is actually sourced from the Audi A4 road car.
Under this aerodynamically sculpted skin is an aerospace-strength steel tube frame chassis, with advanced carbon-Zylon composite crash-protection structures and a 54mm-thick underbody made from blended carbon fibre-reinforced polymer, foam and aluminium plate – all designed to protect the cockpit, battery and fuel tank from high-speed impacts on rough and rocky terrain.
Everything in the Audi RS Q e-tron’s chassis is tightly packaged – including the over 4km of electrical wiring used to connect the elements of the Audi RS Q e-tron’s advanced powertrain. But it all must work together perfectly.
“We have a lot of components that need to be high-performing, lightweight and reliable under extreme conditions,” says Andreas. “We have lots of sensitive electronics and electrical components that we need to protect against sand and water. The interaction of all the powertrain components and the high-voltage battery is extremely complex and we had to make use of every centimetre to accommodate them all in the car. They all have to be attuned to each other perfectly.”
Fine-tuned for perfection
Impressively, only subtle changes were required to adapt Audi’s MGU05 electric motors for the challenges of the Dakar Rally. “Of course, we had to make some modifications, because racing in the desert has different challenges than Formula E,” says Andreas. “There’s the sand, the jumps, the long stages. But we can basically build on the expertise from Formula E and our Le Mans prototypes.”
While the all-electric Formula E single-seater series proved to be the perfect proving ground for the MGU05 – helping Audi develop a lightweight but extremely powerful electric motor with 97% efficiency (more than double that of an internal combustion engine) – the Dakar Rally programme now offers Audi a unique chance to further develop its advanced lithium-ion e-tron battery technology.
“As engineers, we see development potential in every component,” says Stefan Dreyer, Head of Development for motorsport projects at Audi Sport. “With the Formula E drivetrain, we already had an efficiency of 97%. The situation is quite different with the battery. This is where the greatest development potential lies for electromobility. We’re always working closely with our colleagues from road car development on this project, and what we learn from the extremely challenging Dakar project will flow into future e-tron production models.”