23/05/2007
NEWS STORY
Monaco may be the most unusual, most unique race on the Formula 1 calendar, but for the engineers the challenge remains the same: fine-tuning their car to achieve maximum performance around the circuit. Monaco is the most unforgiving circuit on the calendar, and getting the most out of the R27 around the twisty streets will require some rather unusual measures…
Chassis
Ride heights: The roads in the Principality may feel billiard-smooth at the wheel of a road car, but they are the equivalent of cobbles for the rock-hard suspension of a Formula 1 car. The public roads are not only bumpy, but sharply cambered and very slippery – especially on the traffic markings that are dotted around the circuit. The track surface is particularly low grip in the early part of the weekend, and it continues rubbering-in until the final lap of the Grand Prix on Sunday. To cope with the variations in track surface, ride heights are raised between 5 and 7mm relative to the norm.
Suspension: In order to maximise the car's grip, we use softer suspension settings than normal. They help the car to ride the bumps and changes of camber. The surface also means that the wheels must be able to move independently to cope with the bumps, and we soften the anti-roll bars to achieve this. Special attention is paid to suspension camber angles too. We run fairly high negative camber, but not so much as to make the car unstable at the rear in the bumpy, high-speed braking zones. The key objective is to give the driver a neutral, driveable car that he can have confidence in around the circuit.
Aerodynamics: Monaco demands the highest downforce levels of the season. Contrary to popular belief, the primary benefit does not come in the corners, as many of them are taken at such low speeds that mechanical grip is of greater importance. Rather, the gains from high downforce come under braking and acceleration, keeping the car stable into the corners – and ensuring optimum traction on the exit.
Steering angle: The famous hairpin at the Grand Hotel is the tightest of the year – along with the sharp turn at Rascasse. This demands the highest steering angle of the season, some two times greater than anything required in Barcelona. Traction control and the differential are tuned to help the car turn on the throttle, while special notches are usually cut in the top wishbones to ensure the necessary steering lock can be applied.
Tyres: The two types of Bridgestone Potenza tyre used during the weekend will be the ‘soft' and ‘super-soft' compounds. While the ‘soft' compound was used as the softer tyre during the Australian GP weekend, it will be the harder compound during this weekend's race. The ‘super-soft' has not yet been raced, but was tested extensively at Paul Ricard HTTT last week with good results. The same two tyre types will also be used at the next race in Montreal.
Engine
Performance: Superficially, Monaco may seem the least demanding circuit of the year, with just 46.6% of the lap spent at full throttle. Appearances, though, do not reflect reality. The bumpy surface means the engine can easily over-rev if the wheels leave contact with the ground – and special attention will be paid to tuning the control systems to stay within the 19,000 rpm limit. A driveable engine and good torque from very low revs are extremely important, and both are strengths of the RS27.
Gearbox: Closely-spaced gear ratios are used at this circuit in order to optimise acceleration, and get the most from the engine at slow speeds. The gearbox will have to cope with 53 gearchanges per lap – a total of nearly 4150 per lap.
Cooling: With the engine running at full throttle for so little of the time, you might think cooling is not a problem – but you'd be wrong. The engine is only cooled by the car's movement through the air, and the absence of long straights coupled with the slow average lap speed makes cooling tricky. This is exacerbated by the fact that the short gear ratios mean the engine is often running at high revs. Bodywork is therefore sometimes opened up to ensure the engine stays within its operating temperature limits.