Improvements in reliability mean attention is turning to unleashing the true performance of the E22. Lotus F1 Team Technical Director Nick Chester explains all…
What did the team learn in Sepang? We’ve learnt more about our mapping and we’ve made some improvements with the braking of the car, but there is still a lot more to come. We have more work to do at Enstone including improving the set-up and operation of our brake-by-wire system, which is one of the areas where the drivers have the biggest complaints. It’s spoiling their entry into the corner and costing them quite a lot of time.
How does brake by wire work and why is it causing issues? The system looks at what the driver is requesting from the brake pedal and then the demand is split between a braking force generated by the power unit and a normal hydraulic braking force from the callipers. The difficult part is fine tuning those two different types of braking demands so that they work together in a natural, predictable way for the driver. It’s very important to have a brake-by-wire system that responds the way you want and to get the mapping correct so that you have the right braking behaviour to make it easier for the driver to control wheel locking. When you initially apply the brakes you want to get the pressures up high as quickly as you can, for good retardation. But for corner entry, how you come off the brakes is really important. Being able to carry good speed into the corner apex makes a massive difference to the lap time. If we add up all of the laps done with the E22 so far this year, it’s probably the same as the first three days of testing last year… That’s right. We are at a very early stage in terms of understanding of the car so there is a lot of latent potential to be unearthed. We are still exposing reliability weaknesses, but we’re working through these well. The unfortunate aspect is that this has occurred at the races, where we want to be scoring points and building a championship campaign. At the races we’re still doing some work that you would normally do in winter testing. Some of that is obviously due to an enormous regulation change - everybody is still learning - but due to our lack of running we are on a much steeper learning gradient. There is a positive that there are much bigger steps that we can make. An example of that is the improvement in wet qualifying performance this weekend relative to Melbourne.
How frustrating is it to lose track time due to different reliability issues? It is frustrating. Particularly in Malaysia because the build of the cars was very good, but then a software issue let us down and prevented us running in FP1. Both our drivers have been vocal in praising the long hours done by the team at the racetrack. How much longer do the cars take to work on now? The cars are much more complicated this year. There is a lot more involved in the build of the car. Obviously it’s only the second race and things will get easier. We will re-design things to make them easier to fit, the procedures will improve and the mechanics will get more familiar with the components. But even by mid-season, I would say it will still be a harder car to work on than last year. I’m sure that’s the same for all teams.
How happy are you with the upgrades brought to Malaysia? It’s a tricky one to tell because we lost a lot of Friday running, so we didn’t get all the comparisons done that we normally do. We’ll have to do a further comparison in Bahrain to get a proper feeling for how they perform. What are the main challenges for Bahrain? We go there without a lot of mileage in winter testing so we have more set-up work to do on the track. Obviously temperatures can be quite high, so that is one thing we will have to watch out for. Then it’s about getting more of our development parts on the car and doing more work with the power unit.
TECH TALK - E22 SET UP
FRONT WING Front wing settings are optimised around turns six and seven. REAR WING Relatively high levels of downforce are required for Bahrain so the car runs with a lot of rear wing. Not to Monaco levels, but comparable amounts to Albert Park and Malaysia. High temperatures mean less dense and aerodynamically effective air to cleave. SUSPENSION There are reasonable traction demands so the suspension needs to be sufficiently compliant for these requirements. The traction demands from lower speed corners mean a focus on enabling maximum usage of the mechanical grip from the tyres. Kerbs are used in turn two in order to maximise the straightline speed before turn three and the long kerb at the exit of turn 10 is generally avoided because its harshness can hurt traction.BRAKES Bahrain represents the first proper test of braking systems of the season. Long straights lead into slow corners, meaning brake temperatures and wear levels need close monitoring. TYRES Pirelli’s P Zero white medium and yellow soft are nominated. Despite the circuit’s desert domain, the track is not as sandy as you may expect – due to the circuit’s impressive track cleaner! The asphalt has a high abrasiveness which gives good grip but can lead to high tyre degradation. So far the tyres this year have proven to be quite tricky to manage in the races having similar degradation than 2013 despite being a step harder.
ENGINE SET UP With four long straights over the course of the lap the MGU-H will have plenty of opportunity to recharge while the heavy braking points at the end of the straights allow the MGU-K to keep the battery reserve at high charge. The circuit is therefore in the middle of the table on the balance between electrical energy and fuel. One of the major challenges will be the hot temperatures of the Bahrain desert that will put the cooling system of the Energy F1-2014 under a great deal of pressure. With cooling requirements already at a premium with the high rotational speeds of the turbocharger and MGU-H, adding extra external temperatures will make engine cooling a priority task on the job list
