We’re on day one of the Belgian Grand Prix, and, we’re already wistfully thinking of watching grand prix cars blasting down the hill from La Source during Friday practice.
That initial buzz is one of the absolute highlights of our season: the cars quickly gather pace as they blast downhill, drivers rapidly firing through the gears, the engine note screaming off the concrete wall just inches to the right, the throttle absolutely nailed.
Suddenly, the car bottoms out and, without a lift, ascends the sheer Tarmac wall of Eau Rouge – Formula 1’s most iconic corner. At the summit, the car briefly teeters on the horizon and then disappears from view into a seemingly endless wall of forest, the engine note still screaming breathlessly through the pine trees.
But let’s look behind the romance: in Formula 1, nothing beats good, hard data – and here’s some exclusive telemetry traces from Spa (and Monaco and Silverstone – two more of grand prix racing’s ‘grandee’ tracks) and some expert advice from Vodafone McLaren Mercedes engineers to guide you through the intricacies of driving a grand prix car at some of the greatest circuits in the world…
Eau Rouge (Spa Francorchamps)
“Eau Rouge is a big corner and extremely high-g – that’s why the drivers love it. The car does get quite loaded vertically – so it’s a bit of a challenge to set it up in terms of the suspension travel because the compression at the bottom of the hill is quite severe and you get a lot of travel.
“The approach is extremely fast because you’re travelling downhill, rattling up through the gears. You aim for the first kerb on the inside: it’s flat, although you do scrub off speed. I think Lewis tends to take quite a reasonable amount of kerb here.
“Lewis is in seventh on this telemetry, but it’s normally sixth to give you good revs and good power through the corner before selecting seventh at the top of the hill. But it depends on the wind direction – you don’t want to run out of revs at the top of the hill.”
Massenet & Casino (Monaco)
“Massenet [the left-hander] is actually quite a technical corner. Under braking, there is quite a tough bump so the car goes light just as you’re at the top of the hill and about to turn in. You also have to be quite careful on the brakes – there are variable lines that you can take through there.
“Look at the telemetry: Lewis hits the brakes, comes off the throttle, snicks down to fourth gear and takes quite a long apex, hugging the inside. It’s tempting to get too much power on at this point, but do that and you’ll tend to run wide at the exit.
“As you can see, Lewis is quite gentle getting onto the power; he’s feathering it a little bit and has just the right amount of acceleration between the two corners to get himself positioned nicely for the right-hander at Casino.
“Then it’s another dab on the brakes, down into third and he picks up the power nice and gently. There’s also a bump and a rise at the exit of Casino Square, which explains the rise in revs seen on the telemetry; a little bit of a correction – but not too bad. Lewis is very smooth; very careful picking up the throttle.”
“An excellent series of corners. Lewis’s approach is to send the car in as fast as he can, then deal with it later. If he’s got the grip, he’s away; if he hasn’t, he’s got the talent to deal with it. It’s a win-win situation for him.
“For Lewis, the first couple of apices are flat. As he flicks left for the second part of the corner, he lifts off – but not all the way, still keeping some power on – and drops it down a couple of gears into fifth. For the final right-hander, he lifts off again, knocks it back down to fourth and gives it a little tap on the brakes. You’d hardly notice the braking – it’s literally to stabilise the car.
“Again, the exit is critical for speed down the Hangar Straight. Different drivers approach this series of corners in very different ways: look at a trace and the speed differentials across those four apices will be wildly different, but the delta across the whole section of track will be very similar.”
What am I looking at? How to read telemetry
Like musical notation or shorthand, telemetry only reveals its secrets once you’ve learned how to read it.
As with a book, you’re reading from left to right across the page, and you’re studying key instrument traces (throttle/brake/steering etc) to build up a complete picture of how the car, and driver, behaves across the course of a lap.
In these examples, there are six traces:
|Purple (top)||Engine rpm (there are tiny rev fluctuations after each gearshift, that’s a little torsional vibration through the crank|
|Red (stepped)||Gears – vertical lines indicate a shift of gear|
|Light blue||Steering trace – up is left and down is right|
|Red (linear)||Throttle – the uppermost flat-line is full throttle|