Find out what you need to make a school run Q5 45 TFSI work on the Dakar dunes…
By John Howell / Monday, January 10, 2022 / Loading comments
Unfortunately, the PH coffers didn’t stretch to a full Dakar Rally entry this year. Oh well. Bit of a shame, but obviously you can’t have everything you want in life. Nevertheless, we did make it out on the Dakar dunes, courtesy of Audi. The manufacturer is competing this year with three RS Q e-tron cars (more on that in the coming days), and therefore found itself in need of something suitably robust to spirit bigwigs and journalists between stages. A selection of specially adapted Q5 45 TFSI Sportbacks resulted, made by Holzer, a rally and race car firm based in Augsburg. The project leader was Mario Weber, and together we chatted through the changes he’s made before taking a car out to learn the art of driving on sand.
Because they’re intended to run on the Dakar course, these Q5s must conform to FIA race route standards, which aren’t as strict as the race-fit regs. It was a surprise to learn that the Q5’s factory air suspension was deemed strong and capable enough for what’s required; there isn’t even a sump protector, although when the suspension is raised the ground clearance is considered up to par. That said, these are a work in progress. Weber said they’ll assess the cars when they’re back at base, and if there’s more damage underneath than expected, they’ll beef up the underbody protection for next year. That’s when they intend to run the cars along the entire course – for now, it’s just the odd stage.
The standard wheels and tyres had to be swapped for 18-inch Momos shod with 255/18 BFGoodrich All-Terrain KO2 tyres. On the road sections, the pressures are set to 3.5 bar, which is reduced to just 1.0 bar on the sand. I thought the huge sidewalls would add a little bit the ride height, but apparently not – the combined tyre and wheel diameter is the same as a standard 20-inch rim fitted with regular low-profile rubber.
Strapped to the roof is a selection of get-out-of-dune-free cards. This paraphernalia includes a shovel to dig yourself out, sand boards to stick under the tyres for extra traction, a spare wheel (there are two – the other’s inside) and two storage boxes. These contain items like tow ropes, although there’s no winch because you haven’t got a lot to tie onto in the desert. Instead, the cars are sent out in groups, so someone should be able pull you out if required. There’s also a high-lift sand jack. This will raise the car on soft sand if you need to swap a wheel, but it’ll also right the car if you roll it. Weber said you literally prop it against the bodywork, so it’ll destroy the side of the car, but better that than sitting under the blazing desert sun pondering the design of an upturned MLB Evo chassis. There’s an LED lightbar mounted to the front of the roof rack and two LED ‘working’ lights at the back.
There are many more changes inside. For a start, there are two Recaro racing bucket seats with full harnesses mounted to an FIA approved roll cage. It makes getting in and out tricky – put it this way, it reminded me I need to take up yoga to gain some flexibility. The back seats have been ditched for the other spare wheel, two FIA fire extinguishers and two water butts – it’s a requirement to have five litres of water onboard for each occupant. There’s also a cool box, although snacks aren’t an FIA stipulation.
The two digital boxes in front of the passenger are for the race organisers to monitor the car and for navigation. The top one is a Tripy GPS that, like the race cars, receives the Dakar route map on the evening before the stage is run – the route map is kept hush-hush for as long as possible, to stop competitors doing a recce and making pace note. There’s no map, though. All you get is the distance and direction to the next waypoint and, when you arrive, an instruction on which way to go next. It’s up to you to find the path of least resistance between each way point across the never-ending expanse of sand. The Tripy box also monitors speed. The car is limited to 75mph (Dakar Rally cars are limited to 106mph), and if you exceed that for more than 30 seconds the driver’s imposed with fined – around 500 Euros seemed to be the going rate. Weber says you wouldn’t want to go much faster, though. With the off-road tyres on loose sand there’s not a lot of straight-line stability at speed.
Underneath the Tripy GPS is a satellite phone and tracker made by Iritrack. It’s for two-way communication – driver to officials and vice versa – and only for medical emergencies, not for breakdowns. If the car stops for more than two minutes, race control is alerted and rings through to check everything is okay. So if you sojourn for a comfort break, it’s best to remember to hit the green button that tells them all’s well. Otherwise, some official people get cross, which probably means another fine.
Right, so on to the driving bit. Setting off into the dunes, the first requirement is sticking the car in off-road mode and turning off all the electronic gubbins – lane assist, ESP and traction control etc. That means you won’t limit the 45 TFSI 2.0-litre’s free-revving capability, which you want at the ready to keep moving. That’s the one of the golden rules of driving on sand – maintain forward momentum at all costs. A steady throttle is best, with well-judged speed: too fast and you risk taking off and landing with a bang; too slow and you’ll sink.
A top tip for climbing dunes is follow the direction of the wind. The wind does two things: it carries the sand up the gradient, shallowing the angle of accent, and it compacts the terrain. Go the other side and the climb will be steeper and the going softer, and the chance of making it to the top slips away like grains of sand through fingers. As you approach the summit, cross the peak diagonally – to reduce the chance of bottoming out – and then stop, but only once the bulk of the car’s over the precipice. You can never tell how steep the drop will be, so it’s due diligence to check it’s not more than you bargained for, and you need gravity on your side to get going again. If you stop on an upward incline, you’re almost certainly going to dig in.
It’s best to attack really steep gradients at 45 degrees and don’t let the car slide sideways – once it goes you risk dragging a tyre off the rim or, worse still, rolling and having to get the sand jack out. And nobody wants that, especially Weber. If it does start sliding sideways, steer the car so it’s pointing straight down the slope and pray you can stop it. The other rule is to avoid clumps of camel grass like they’re Semtex. This is generally the only vegetation you see in these parts and it’s perfect for hiding rocks that could rip the suspension off. Even the best get caught out, as reigning Dakar champion, Stéphane Peterhansel proved. He ran through camel grass on Stage 1. It promptly ripped off the entire left rear corner off his Audi RS Q e-tron and that was him out of contention this year.
Weber was right when he said the car moves around a hell of a lot on the sand. Without any steering input it wriggles like a snake and he says the trick is to “let the car find its own way.” In other words, don’t correct it unless it goes full-on sideways. When you want it to turn, the steering response is pretty lax so a quick lift starts the rear moving and turns the car quicker. Another trick to get the car rotating is clip the smaller dunes like you would an inside kerb at Brands Hatch. This pushes the weight onto the outside wheels for more bite. It’s all about understanding the terrain, using it to your advantage and, above all, always respecting it. Weber summed it up as “surf the sand like it’s a wave,” which marks him down a poet and a talented engineer. He was also a thoroughly lovely bloke and infectiously enthusiastic. I liked him a lot, and his dune buggy
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