Renault's tech file - Montreal

Montreal’s Circuit Gilles Villeneuve is a stop-start, temporary circuit. The long straights mean plenty of heavy braking, while numerous slow corners put the emphasis on strong traction and good engine torque to launch the cars out of them. A competitive car will give the drivers confidence to brake late, while also looking after the rear tyres on a circuit where teams will be running the softest of Bridgestone’s 2007 compounds.

Aerodynamics

Montreal will see all teams debut a new ‘low downforce’ aerodynamic package. The circuit can be considered as including no high-speed corners, as turn 5 is taken comfortably at full throttle in fifth and sixth gears. The primary focus for the aerodynamicists is therefore on minimising drag levels in order to achieve competitive straightline speeds (with a maximum over 320 kph), while the downforce will assist vehicle stability under heavy braking, as well as in the slow-speed chicanes. The low downforce levels mean the car feels light to drive, and nervous under braking. This means the drivers need to be more delicate with their steering inputs, and when applying the brakes and throttle.

Suspension

The cars need a responsive change of direction in the chicanes while maintaining good stability under braking and traction out of the slow corners. Brake locking must also be taken into consideration when tuning the suspension, as excessive locking at front or rear will cost lap-time.

Brakes

After Bahrain, Montreal is the most demanding circuit of the year for the brakes. Overheating is not the primary concern, as the discs and pads have ample time to cool on the straights. However, the braking energies are very high, with four braking events from over 300 kph – and the other two from above 250 kph. Basic wear is therefore our primary concern, and we monitor this in real time during the race. We may ask the driver to adjust the brake balance if wear levels become alarming at front or rear, and some of our work in practice will focus on ensuring that brake wear levels are under control on representative race fuel loads.

Tyres

The temporary nature of the circuit means that the circuit begins the weekend very ‘green’ and grip levels improve constantly throughout the weekend – just like we see at similar venues such as Melbourne or Monaco. The track surface is not particularly abrasive, and the absence of high-speed corners means that tyre energies are among the lowest of the season. Consequently, the teams will be using the Soft and Super-soft compounds from Bridgestone’s 2007 range.

Strategy

Traditionally, Montreal has been a race at which strategies ranging from one to three stops were possible – although a two-stop strategy is likely to be the most competitive solution under the 2007 tyre regulations, as it has been at every other circuit this year. The absence of high-speed corners means the fuel effect (the time penalty for carrying fuel weight) is relatively low at this circuit, and combined with low fuel consumption (similar to Budapest), this means there is relatively little penalty in qualifying for carrying extra fuel. The low fuel effect also means that a one-stop strategy is potentially competitive, but its effectiveness in 2007 will depend on how well the super-soft tyre stands up on race day.

Engine Performance

The engine is used in a very stop-start fashion around the Montreal circuit, which is essentially compromised of six extended full throttle bursts separated by chicanes. The engine spends over 60% of the lap at full throttle, which is not a particularly high percentage, but the longest full throttle section last for 14s – a more demanding value, that puts the circuit at the higher end of the scale for engine severity. Our selection of final drive ratio must take into account possible shifts in wind direction down the back straight; should it be too short, then we will spend too much time in the 19,000 rpm rev limiter – and this will cost us lap-time. Cooling is not normally a problem thanks to the long straights, but cut grass and other debris are potential hazards. We monitor temperatures closely, and debris can usually be removed at the pit-stops.