Just like any racing car, but more so, a Formula 1 car is like a living organism in the way it requires constant attention just to keep it functioning. The engine oil needs to be pre-warmed as do the tires, yet heat must be diverted away from other components. The brakes don't start working properly until the carbon-fiber discs are at around 932 degrees F, yet get them much above 1,472 degrees F for any length of time and they will oxidize, heating themselves out of existence as the air passes over them.
There are tiny operating parameters and everything requires constant monitoring and input. F1 cars are ridiculously sensitive, highly strung thoroughbreds that sit on a knife-edge of equilibrium that is constantly evolving – which is just as it should be. F1 isn't supposed to be easy or simple.
But for all that the processes are maintained on a knife-edge, the car must never feel like that to the driver. For him to do his best stuff requires the car beneath him to feel malleable, responsive to his every input with a fidelity that allows him to not even think about the mechanics of it all. The limit should be a place he can sit on with impunity while expressing his competitive desire. That's all about finding the appropriate setup.
Push the car hard enough and one end of it or the other runs out of grip. Which end and how predictable is the transition is what allows the driver to access that limit according to his personal preferences. But because of that trait of everything being in a state of evolution – the track, the car's specification from one race to the next, variations in track layout, etc. – that sweet spot needs to be constantly found and re-found. Adjustment of myriad setup tools – from simple suspension rates, tire pressures or front and rear wing levels to the more subtle aids of steering ratios, brake master cylinders, ride heights and an apparently limitless variety of electronic settings for engine, engine braking and differential settings – help the driver to find that place, with the aid of his race engineer and vehicle dynamicists.
A team used to arrive at a track with the setup spectrum theoretically unlimited but the tools for where on that spectrum to choose – the driver's feel and the intuitive knowledge of his engineer – still fairly basic. Today, with the huge advances made in simulation, a team arrives with 90 percent – maybe more – of the setup already defined. The big chunk of setup-derived lap time is done at the factory beforehand so that, at the track, the driver is working within parameters that can influence things only by a few tenths of a second.
Dave Greenwood is Marussia Virgin's chief engineer and was a vehicle dynamicist at the Renault team when it last won the World Championship, in 2006. He explains: “The aero levels most appropriate to the circuit and the ride-height range are set at the factory. The damping rates are set then, too, on the seven-post rig or on the simulated seven-poster. This is because the packaging of an F1 car is so tight that it would just be impractical to be changing dampers during the limited amount of running time you have on a grand prix weekend. It would be a nightmare. So what the driver has to play with at the track is a little bit of front wing flap angle, the spring rates and the various electronic settings.
“But you still need to check with the driver at the track, because the simulation is ‘perfect world.' For example, from India, a track with a lot of high-speed, long-duration corners, we arrived at Abu Dhabi, a track with mainly slow corners, so we ran a lower rear ride height because the car isn't being pressed down so much and you want braking stability into slow corners. But the driver might try it and find that, actually, the part of the track where he most needs help is one of the higher-speed corners, so lowering the ride height will find him more lap time than he loses from any change in braking stability.
“Simulation still isn't perfect,” Greenwood continues, “and a computer-simulated lap – as opposed to the driver doing a lap in the simulator – will drive the car with more of an oversteer setup than a driver would, and get a quicker lap time. But in the real world it would be too much for the driver to hang on to.”
That says quite a lot coming from a guy who runs Timo Glock (RIGHT), an F1 driver with one of the most rally driver-like styles! But Greenwood's point is well made: The more oversteer a driver is comfortable with, the quicker the setup he can run. McLaren's technical director Paddy Lowe explains further: “We see from the data that Lewis [Hamilton] is fantastic at controlling oversteer. He can have massive levels of steering correction – to the extent that other drivers would be bitching like hell that the car was undrivable – and Lewis won't even mention it. With a driver like that, you're better equipped to push the boundaries to new levels.
“A lot of the performance limit of a car is set by stability; if your driver can't hang on to it, you have to introduce understeer in that zone. If you have a driver better able to deal with oversteer in zones that induce it, you'll have a less understeery car elsewhere and therefore more total grip over the whole lap. The great drivers – Ayrton Senna, Nigel Mansell, Michael Schumacher – all had that ability. Like-for-like, compared with other drivers, they wanted more front end.”
So elementary is Hamilton's ease with this trait, it caused McLaren to rethink the range in which its car could be set up. Pat Fry, now Ferrari's technical director, was at McLaren back in the winter of 2007-'08 and working with Lowe in getting out of the setup loop they had evolved over the years.
“We spent the whole of that winter changing the basic traits of our cars so that we'd no longer be so limited by understeer in slow corners,” recalls Fry, “and it took us all that time to get it to the point where we could run it like McLaren does now.
“At Ferrari, we're still in the same loop as McLaren was before we changed – and in 2011 that's hurt us as the blown diffusers have become more powerful. They generate a lot more grip obviously, but it's at the rear, so you need to have in your setup toolbox something that compensates for that, not just increase your understeer. And we've sort of run out of options at that end.”
But while dialing in as much oversteer as the driver can cope with will make for quick qualifying laps, it's not as simple as that once you introduce the complication of tire life to the equation and when the parc ferme regulations prevent you from having one setup for qualifying and another for the race. This year's Pirelli tires are weaker at the rear than the front, and so they often need protection from the setup. The title-winning Red Bull RB7 has been particularly hard on rubber – mainly on account of going faster than the others! – and, in several races, World Champion Sebastian Vettel had to live with more understeer than he'd ideally have chosen, just to limit the loads being put through the rears.
The way that Jenson Button's feel allows him to measure out tire life has also played its part in allowing him to be more competitive with teammate Hamilton than was the case last year. Hamilton's setups induce more performance degradation of the rear tires than Button's who can thereby lap fast for longer. This is what would have allowed him to beat Hamilton to the checkered flag at this year's Hungarian Grand Prix, irrespective of Hamilton's drive-through penalty.
The balance changes through a race, not only through tire performance but also the reducing fuel load. A full-tank car will tend to understeer, moving toward oversteer as the fuel load lightens. Obviously the setup has to take account of this as there are only a limited number of ways the driver has of changing things from the cockpit. The most significant of these are the differential settings, varying the pre-load via controls on the steering wheel. These are typically variable in three parts, comprising corner entry, mid-corner and corner exit. Greater locking of the diff gives better traction but more understeer on entry, especially in slower turns. Last year, the Lotus, HRT and Virgin teams all used an inadequate hydraulics system that came as part of a package with the Cosworth engine. Among its many failings was that it could not generate enough pressure to lock the diff at certain critical loads, giving those cars traction limitations as well as stability issues in higher-speed corners.
A race stint invariably brings further imperfections to setups mapped in the perfect conditions of simulation. At the Korean Grand Prix this year, Hamilton was finding increasing understeer and the team could see on the telemetry that there was a 10-point reduction in front downforce (measured by load sensors on the car). The explanation was only discovered post-race: the front wing slot gap was partially sealed by congealed rubber picked up from the track.
The aerodynamically crucial floors also degrade in performance through a race as their edges are rubbed on the track surface. A lot of attention is devoted to smoothing their extremities and they're covered with a silicon spray, making them more slippery to the air. Typically, aero losses from the floor alone from the start of the race to the end are in the order of 15-20 points – a difference of around 0.2sec per lap.
In a sport so machinery-dependent, we never get a definitive answer on which driver is actually doing the best job of pressing the pedals and turning the wheel. But achieving the optimum setup is inextricably linked with that skill set, the place where the visceral skills of the driver and the cerebral qualities of the engineer come together.
• For the full version of this feature article, plus much more, check out the January 2012 issue of RACER magazine, which is NOT available on newsstands. CLICK HERE to subscribe.