DTM to Dakar: the story behind Audi's rally raider

DTM to Dakar: the story behind Audi's rally raider

Autocar

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Having quit the DTM and Formula E, Audi had many spare engineers and proven parts lying around. Enter the RS Q E-tron

Picture the scene at Audi head office. The company is no longer racing in the DTM and has withdrawn from Formula E. Both announcements meant there were presumably a lot of race engineers standing idly around wondering what to do with all the make-things-go-faster stuff.

Then someone hit on a bright idea: why not put it all into a Dakar Rally car? So here it is: the Audi RS Q E-tron, possibly the world’s most recycled racing car. Talk about being on-message with the climate agenda.

The RS Q E-tron is also, as you would expect from a German manufacturer, one hell of a statement of intent. Although its road car implications aren’t clear at the moment (or at least aren’t being spoken about officially), it is apparent that, with the investment and technology being packed within its tubular spaceframe, Audi would be mad not to use it for a wider ultimate purpose.

A few details, then. Designed for Dakar’s T1-U regulations (a new class that the event organisers hope will mean 100% of vehicles by 2030 will be low-emissions), the RS Q E-trons are being constructed at Audi’s Neuburg site, in the same building that was designed to house Audi’s now-mothballed LMP1 endurance racing programme.

Despite the recycling, Audi is quick to acknowledge that the project carries risk. “It’s the most complex car we’ve ever done,” according to Julius Seebach, managing director of Audi Sport. “An LMP1-plus,” is how Stefan Dreyer, head of powertrain development, puts it. At its heart are four power plants: three electric motors, weighing 33kg each (one to act as generator, the others to power the front and rear axles, and all three nicked from Formula E), and one mid-mounted petrol engine. This is a turbocharged four-cylinder 2.0-litre petrol unit taken from Audi’s DTM race car. The drive element, then, is electric, with the engine purely as a power source to charge the battery – the ‘energy converter’. The motors have a single-speed gearbox, with a slip clutch in place so that the revs don’t run away over jumps. Total power is 386bhp, and that’s dictated by the rules.

The engine runs at a series of predefined consistent RPM figures to make it as efficient as possible. Whereas Dakar cars normally run with anywhere up to 600 litres in their fuel tanks to get to the end of some brutally long stages, the RS Q E-tron makes do with a tank half that size. This is where you can see an element of tech transferring to road car use (senior members of the team were eulogising about how economical it is), because the way it’s being used is so much more efficient than a road car, with the latter’s requirements to run at a broad spread of revs.

“It has low fuel consumption and low emissions,” according to Sven Quandt, Dakar veteran and boss of the Q Motorsport team Audi is collaborating with. “It removes range anxiety and means we’re not overloading the electricity grid, so it’s interesting.” The battery isn’t recycled. It is a bespoke 50kWh liquid-cooled pack, featuring 13 modules and 266 cells, and is located under the drivers. Weighing 365kg wet, it sits on a plate (more on that in a tick) so it’s easy to drop it out from underneath the car. 

One interesting thing: the battery isn’t built by Audi. The firm is remaining tight-lipped as to who its partner is on this element, but I find it curious that Audi doesn’t do this in-house given how much battery knowledge it must have.

All of the above is housed within a tubular spaceframe chassis. You might expect that to feel a bit 1976, when Formula 1 has been using carbonfibre monocoques since 1981, but there are sound reasons. Being illegal under Dakar rules, a carbonfibre tub was ruled out, but there are also practical reasons for Audi doing what it’s done. A tub would be too stiff for Dakar and you need some give in the chassis so that the driver and co-driver don’t get pounded to mush over the harsh terrain. 

But there are still carbonfibre elements to the RS Q E-tron, in that the battery and motors are mounted on huge, 20mm-thick carbonfibre plates that slot up into the spaceframe chassis and are protected by alloy/foam sheets. This achieves two things: it makes the parts easy to swap out and it gives more flexibility to the packaging than you would expect with a standard tubular chassis. But it does run the risk of things getting too stiff. 

As such, they’re controversial. Quandt was very nervous about them at the start of the project. He says: “We linked all the areas [of the chassis] with carbon plates. This is a new idea, but I was sceptical about them because the chassis moves and these are rigid carbon plates. But honestly, now I’m very happy with how they’ve performed.”

There are single shocks all round. A twin- shock set-up was investigated, but the weight was an issue (Audi readily acknowledges that the two-tonne-plus car needs to go on a diet, but reliability has been prioritised over weight-saving), so singles it was. And besides, suspension travel is the real key. “If you have more suspension travel, you will be faster than a car with 100bhp more power,” claims Quandt.

The total size of the RS Q E-tron? 4500mm long, 1950mm high and 2300mm wide, with a 3080mm wheelbase for its wheel-at-each-corner stance. To give you an idea of perspective, that’s a little bit shorter than the BMW 3 Series but nearly 10cm taller and wider than the Range Rover.

As ever, the key to all this will be reliability. That’s partly why Audi has done what it has done: the parts are proven and, in a programme that has been going for only 12 months, testing and development time has been woefully short.

Software is going to be the big headache, as Quandt points out: “We have four separate systems that have to be taught to communicate with each other. It’s been a big challenge.” Indeed, on top of the usual coding complexity, these systems will be constantly pounded by dust and vibration.

Not that the conditions have helped the relatively well-proven engine, either. The temperatures and humidity in Saudi Arabia vary wildly over the course of a day, and this, combined with the altitude changes the car will experience, made operating range a big challenge in the 8500 kilometres of testing that the team has done.

Even with the might of Audi behind it, the team is realistic about its chances. “To finish is a victory,” says Quandt. The team is hoping for stage wins and would count that as a result. 

That’s not to say it isn’t competitive, though. After all, in Stéphane Peterhansel, Carlos Sainz and Mattias Ekström, Audi has three drivers on board who are very familiar with the top step. Peterhansel and Sainz are seasoned pros at Dakar. The former has won the event a record 14 times, using both bikes and cars, while Sainz has triumphed three times. You’ve got to feel a bit sorry for Ekström: while he’s certainly not short of talent, even Audi’s promotional video lists him as a “one-time Dakar participant”.

But as you would expect from a man who has notched up titles in series as varied as the DTM and the World Rallycross Championship, he’s not overawed. “The others are legends, but it’s nice to feel the rookie,” says the Swede. “I’ve learned more in the past 12 months than ever before, but we’ve been doing a lot of days [of testing], and by day three I felt better. I got into eat-sleep-repeat mode. Sleep is the best recipe: if you cheat on sleep, you pay the price.”

Not that he hasn’t experienced some issues: “Toilet logistics on a long day are... interesting. I’ve always been picky about this.” The Audi’s unique powertrain has helped him and co-driver Emil Bergkvist. “The big difference is that there’s no gearbox, so you can’t stall the engine,” he says. It helps in the sand, because you don’t bog down over the dunes as much.”

It’s something that all the drivers have found helpful, to the point that they’re all bullish about their prospects in the dunes. With its single-speed gearbox and instant torque, it’s far more controllable on sand. Peterhansel says: “It’s more fun. I can focus on my driving, because it’s not the most complicated [machine to drive]. It felt smoother, and you can really surf on the dunes.” 

Sainz has enjoyed the fact that “you don’t have to change or select gear in the dunes, which means you can concentrate on the line and driving”. Given that quite a few cars got lost on the Dakar last year, that’s maybe no bad thing. Not that the RS Q E-tron hasn’t been without its issues, as Peterhansel explains: “The problem has been the braking, because you can feel the weight. It’s better than I expected, because of the regenerative braking, but you can still feel the weight.”

You get the impression that all three drivers, but especially Peterhansel and Sainz, were vital to getting this project off the ground in 12 months. In our brief day with the team, Sainz came across as the punchier of the trio (“I’m impatient. The challenge was even bigger than I thought”), but the way they’ve all collectively driven it forward must have been impressive. They’ve all made myriad suggestions and improvements, even down to chucking out the off- the-shelf seats and fitting bespoke moulded ones.

We headed down to the test track to see the car in action at the end of the day, with Sainz at the wheel. His commitment was mighty, both with his speed into the corners and the amount of time he spent pounding round. The gathered crowd felt sorry for his co-driver, Lucas Cruz: given that it was a loop of a few hundred metres around a Tarmac track, the navigation notes presumably got a bit repetitive.

But that’s an indication of the potential of this team. Yes, it’s bankrolled by Audi’s massive budgets, but even on a media day they’re out in the freezing conditions, testing, testing, testing, trying to get ahead of where they need to be come 1 January and the start of the event in Jeddah.

Will it work? Hopefully. Are we witnessing a new era of rally-raid events? Considering all of the experience wrapped up in the team, it’s difficult to imagine not.

-Who will Audi face? -

Although Audi will have only one rival in the T1 Ultimate class (GCK, which runs on biofuels), there are others that will join it in the campaign for the overall win. Prodrive has entered with the Hunter (pictured) and, given the firm’s rally heritage and fifth-place finish last year, must start as one of the favourites. Then there’s Toyota with the GR DKR Hilux T1+, which represents “the biggest technological leap” since the firm returned in 2011. It won in 2019 and features a strong and experienced driver line-up. And last year’s winner, X-Raid’s Mini All4 Racing challenger, returns, but how much the team will miss its two star drivers (Peterhansel and Sainz) remains to be seen. One thing is for sure, though: given the duration of the Dakar Rally, the term ‘favourite’ doesn’t mean much.

-Various categories of the Dakar Rally-

*Motorbikes*

Most riders are amateurs, but the Elite category is the one to watch for. You can tell them apart by their distinctive yellow numberplates. All bikes are limited to 450cc.

*Quads*

Quad bikes come in two varieties on the Dakar Rally: two- or four-wheel drive. The former type is restricted to 750cc, the latter to 900cc. The entry fees for quads and bikes are the same, at €15,700.

*Lightweight vehicles*

This combines two categories: T3 for prototypes and T4 for anything based on a production vehicle, known as a side-by-side vehicle (SSV). Basically, Can-Am buggies and their ilk. With 130-litre tanks, they stop at the same fuel stations as the bikes.

*Cars*

Here’s where it starts to get complicated. T1 is the most popular class, but even within that there are sub-categories, such as T1+ and T1 Ultimate, the latter of which Audi runs in and is designed to promote entries from alternatively fuelled vehicles. T1+ is for the likes of Toyota and this year allows for more suspension travel and bigger tyres – a concession to Toyota and Prodrive to permit some of the things that Audi is allowed in T1-U. Essentially, though, these are all prototypes so tend to win overall. Then there’s T2, based on production off-road vehicles but modified with a healthy dose of safety kit; and Open for cars like those used in the American Score series.

*Trucks*

Comprising T5.1, T5.2 and T5.3 types, these are the tortoises to the other hares. T5.1 trucks are quite rare now, because they’re production-based so rubbish over dunes. A T5.2 truck is a full prototype, built for speed and with a ‘cargo hold’ that’s almost always empty. T5.3s are the rapid support vehicles that serve as rolling workshops

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