Decoding the Red Bull engine map controversy

Sky Sports F1's Mark Hughes delves into the engine mapping controversy that surrounded Red Bull at Hockenheim and explains why it was a classic case of F1 pull and counter pull...

Red Bull's controversial Hockenheim engine map was fully legal, a fact now accepted by the FIA's technical delegate Charlie Whiting. It broke the intent of the regulations, but not the wording - and that's a completely legitimate avenue of competition in F1 and always has been. Motorsport, and F1 in particular, has its own code of technical ethics. The regulations are not there to be blindly followed in their intent by the competitors. They are merely the worded limitations to be worked around, and an intrinsic part of the game is to find advantages over rivals by getting around the intended limitations without breaking the wording. Only those who don't realise that this is an essential part of the competition - or rivals who have been competitively disadvantaged - would consider such action as cheating. Once a competitor has thought of a way around a regulation it is then the FIA's responsibility to rein them back in with a revised wording. So we see a constant participant pull and governing body counter-pull around the regulations and this process has been on-going since the sport was invented in 1895. Some have pondered why it always seems to be Red Bull falling foul of the FIA for its interpretation of regulations and the answer to that is quite simple: in the last few seasons it has more often figured out a way past the intent of the wording than others. Red Bull has been surrounded in technical controversy more often because it has had more ideas. So what was it doing to create such controversy at Hockenheim? They're not about to tell us and thereby neutralise the benefit of their recent work, but we can take an educated guess - based partly on Jo Bauer's statement before, and that of the race stewards' after, listening to the team presenting its case. The engine map used in Germany gave the engine 'significantly less' torque in a specific mid-range part of the rev band at full throttle than the same engine had produced in earlier races. Bauer said that he believed this contravened regulation 5.5.3, namely: "The maximum accelerator pedal travel position must correspond to an engine torque demand equal to or greater than the maximum engine torque at the measured engine speed." In other words it is not permitted to have the engine give less torque than that being asked by the driver through the throttle pedal - at a given engine speed. Engine speed and throttle position are related, but are not the same, because engine speed changes cannot be instantaneous. Hence the reference to 'torque demand' in the regs - the torque demand is the position of the throttle pedal. Furthermore, engine speed and power are related but are not the same, because the throttle pedal directly controls only the air/fuel flow and that's only one of three parts of the combustion process, the other two being ignition and mixture. How the ignition timing is related to the engine's speed, load and throttle position is controlled by the engine's electronic map. By using the map to retard the ignition at key points, it is possible to have the engine produce less torque than it is capable of in chosen parts of the rev range. This is what Red Bull's Hockenheim map was doing. Bauer considered that this was in contravention of regulation 5.5.3. By giving less torque at certain engine speeds than he had already seen the engine give in previous events, he considered that the new map had thereby reduced the engine's torque - ie it did not 'correspond to an engine torque demand equal or greater than the maximum engine torque' at certain revs. Going by what the regulations were supposed to have meant, Red Bull had contravened them. Going by what they actually said, they had not. Reducing the torque demand at full throttle from one race to the next is very different from reducing the full-throttle torque demand of the engine on that day as a certain engine speed is reached. Red Bull chose to read the regulation in a way that meant the latter - and its map did not contravene that reading. The FIA meant torque demand relative to what the engine is ultimately capable of. Red Bull chose it to mean torque demand relative to what that engine was capable of with that map on that day - and on those terms there was no reduction, and therefore no offence. Regulation 5.5.5 determines how the torque demand map must progress through the engine speed range. 'At any given engine speed the driver torque demand map must be monotonically increasing for an increase in accelerator pedal position.' 'Monotonically increasing' simply means that it is not allowed to decrease at any point on the curve - but can straight line within a general overall increase. The torque demand is not allowed to decrease as engine revs increase. The Red Bull map cleared this requirement. That's the nitty-gritty of the wording, and Red Bull's interpretation was accepted as valid by the stewards. But why on earth would a team be trying to reduce the torque of an engine? It's all about trying to find a way of blowing the diffuser under the new regulations. If you can get the map to arrange the ignition timing so that with the accelerator pedal full to the floor, at a certain rev range the engine's throttle bodies are pumping air through the combustion chamber and exhaust after the mixture has already been ignited, then you will sacrifice some potential torque but you will gain flow through the exhausts which are positioned to direct the flow to the downforce-inducing rear brake ducts and the sides of the diffuser. This development will have been designed to complement the 'Helmholz exhaust chamber' introduced by the team at the previous race of Silverstone. This is a cylindrical enclosed chamber within the exhaust arrangement. The diameter and design of the pipes are such that with the gases flowing through there as the driver is on the throttle, the pressure builds and fills the chamber. When the driver releases the throttle under braking or into a bend, the pressure reduces and this allows the gases that have accumulated in the chamber to be released - giving some additional exhaust flow to the downforce-producing brake ducts and diffuser and thereby a measure of 'off-throttle blowing'. So with the Helmholz chamber giving a brief moment of off-throttle blowing and the engine map enhancing the on-throttle blowing, the RB8 will have received an all-round increase in downforce at only a small cost in engine performance. All whilst meeting the letter of the rules.