Turkish GP: Renault technical preview

Renault Turkish GP Tech File

The Turkish GP will mark the start of the final third of the 2007 championship. Round 12 of the season is likely to be held in extremely high temperatures on the newest circuit on the calendar. It's a track that drivers and engineers enjoy, thanks to a challenging layout that combines slow corners, long straights, changes in gradient and turn 8, among the most difficult corners of the entire season.

Chassis

The 14-turn Istanbul Park circuit is typical of the modern layouts, typified by the circuits in Bahrain and Shanghai, in that it features an extremely long straight which means top speed is a critical performance factor in determining a good race set-up. Ideally, teams would run more downforce than they are able to, in order to gain time through the high- and medium-speed corners, but the long straight after turn 10 shifts the compromise towards a low-medium set-up in order to achieve competitive top speeds -- and to allow the drivers either to overtake, or defend their position against rivals.

The circuit is the newest on the calendar, and still in good condition. The surface is generally smooth and the kerbs are not particularly aggressive. This allows the engineers to use relatively stiff suspension settings and low ride heights to optimise aerodynamic performance, to achieve a good change of direction in the technical portions and to give good stability in the high-speed corners. The only exception to this is in turn 8, where several large bumps can disrupt the car and cause oversteer. Generally, the drivers adjust their line to avoid the bumps, rather than compromising the car set-up to cope with them.

The braking demands of the circuit are not particularly severe in overall terms, but the braking zone into turn 12 is critical as this is the main overtaking opportunity. The drivers must be able to attack this braking event with confidence when battling wheel-to-wheel, while overshooting the corner can be very costly on a timed lap.

The overall energy put through the tyres in Istanbul is close to that seen in Silverstone, and Bridgestone will make available the same combination of medium and hard compound tyres as it did for the British Grand Prix. We pay particular attention to the front tyres, and the right-front in particular, as they have a very hard time in the long, high-speed turn 8.

Engine

In common with the more modern circuits, Istanbul Park is a demanding and varied challenge for the engine. Approximately 67% of the lap is spent at full throttle, a figure that is well above average, and the circuit also includes a long period of around 16 seconds spent at full throttle, between turns 10 and 12. The engine must be tractable, pulling strongly from low revs all the way to its 19,000 rpm limit, while power delivery at high revs is also fine-tuned to avoid upsetting the car balance in turn 8.

It is important to ensure the power train is well-cooled, but we are familiar with the engine's needs at this stage of the season. The circuit features no prolonged, slow-speed sections which might cause overheating, and the long straights mean that the car is well cooled.

-credit: renault