As a 21-race calendar, the Formula 1 World Championship provides all sorts of different tests for a car. Each venue offers something unique, a different set of challenges to deal with.
Fresh from one such challenge in Monaco, we head to another very different proposition at the Canadian Grand Prix. The Circuit Gilles Villeneuve is a long, thin, high-speed venue on a man-made island - the Ile Notre Dame - on the St Lawrence River.
When broken down into the most basic terms, the Montreal track is almost exclusively made up of long straights and chicanes, with a hairpin for good measure leading onto the longest flat-out section on the circuit. And all of those aspects mean getting the power down is a key factor in delivering strong performance.
“Every aspect of the power unit is important, but top speed is very important because of the long straights,” Performance Engineer Hideomi Mori says of racing in Canada. “To reach top speed you also need traction out of the corners, so that is crucial.
“It’s not only Canada where you need to focus on that, because even somewhere like Monaco which has lots of slow speed corners and then hard acceleration, good traction is important.”
The fact that there are other venues - with very different layouts - that place similar demands on traction means the power unit is not actually run all that differently compared to other circuits. Yet the impact of a problem would be magnified during a long straight if acceleration had been affected.
“The current power unit has a turbocharger,” Mori-san explains. “So between the turbocharger and the internal combustion engine sometimes there is a lag - what we call turbo lag, when there is a hesitation between the driver pressing the throttle pedal and the power coming in - and if this lag is too big then the driver will find it difficult to modulate the power using the throttle pedal.”
Put simply, the turbocharger forces more air into the internal combustion engine (ICE) in order to increase the power output from each cycle. The extra compressed air enters the inlet manifold at an increased pressure to the air that would be in the inlet manifold without the use of a turbocharger, and this difference in normal atmospheric pressure and the extra air pressure created by the turbocharger is described as the boost.
Engine manufacturers set a target of the additional pressure they would like entering the inlet manifold, which will then lead to a certain level of power output. “If the driver feels he is not getting enough torque, then we do have the ability to slightly increase the boost, so that the torque can follow on target, which should make the driver happy,” says Mori-san.
All of this contributes to what we often hear drivers describe as the drivability of a power unit. Smooth, predictable power delivery is what the driver wants, as close to instantaneous as possible. With higher boost pressure comes a more noticeable difference if there is any turbo lag, but the power unit’s many energy systems are used to compensate.
“Honestly we’re at the point now where, from the driver’s point of view power delivery is very seamless,” Brendon Hartley explains. “There’s a few tools that we can manage from the cockpit, but for the most part, pressing the throttle pedal from 0 to100% gives you 0-100% of the available power.
“There’s a lot of complicated systems and programming going on behind the scenes, with the engineers analyzing all the data and getting all this to work seamlessly, but from a driver’s point of view sitting being the wheel, you are not really aware that there’s so much going on with energy recovery, from the MGU-H and the MGU-K. All you feel is a huge amount of power going to the rear axle, which is great.”
If a driver isn’t getting consistent power delivery when accelerating out of a corner, he is more likely to spin the wheels and damage his rear tyres. But even if the throttle is as responsive as the driver wants it to be, it is still in his hands to modulate the pedal and get the best acceleration possible.
“Current FIA regulations don’t allow traction control on the ECU, so we cannot have automatic traction control,” Mori-san points out. “From the free practice results and the driver’s comments we do tune the boost settings so the driver gets what he wants at each corner. If we saw massive wheelspin, then basically the driver can manage the traction by himself. It’s definitely more on the driver than on the settings.”
But there’s more to putting the power down than simply the way the power unit is being operated. The greater the vertical load on the rear tyres, the less likely they are to spin, and that means the level of downforce also has an impact.
“More downforce means the car will stick to the road better. In Canada we have low downforce to help top speed, because you want as little drag as possible on the long straights. Sometimes you are working with the car engineers to balance how much downforce you have because a higher level will help traction but hurt top speed.
“A lot of this work is done on the simulator. In pre-event preparation we also carry out dyno testing to check from a torque control point of view. The driver is the most important point of feedback, and not only after FP1, but even during the session. If he has complaints we can re-tune the power unit and change other settings as we go. We sometimes suggest other settings during the session to make improvements.”
While Monaco put emphasis on traction, Canada is more of a compromise for the settings due to the top speed requirements. And while the streets of Monte Carlo place all the emphasis on strong qualifying performance - with overtaking at a premium - the same can’t be said of Montreal.
“In qualifying we just go for maximum performance but in the race in Canada there is a high chance of overtaking on the long straights. So we need to prepare different modes in order to focus on the long straights, where we need to deploy more energy. These modes do not give the fastest lap time, but they are needed during the race to allow a driver to overtake and to avoid being overtaken.
“For that you also react to the performance of other cars as well as your own. The team has past data relating to overtaking at this track, so we share those results and discuss how much energy we will need in different places, and where we perhaps don’t need so much.”
Every grand prix a new challenge. That’s what makes F1 so demanding, and that’s why we race.