Malaysian GP: Williams technical preview

Car dynamics

Average turn angle indicates the average angle of a circuit's corners expressed in degrees. The higher the average turn angle, the more acute corners in the circuit configuration and hence the greater propensity for understeer to compromise lap time. At Sepang, the average turn angle is 1390, against a season average of 1100, ranking as the circuit with the highest average turn angle across the Championship. As a consequence of the circuit's physical layout, an understeering car balance will have a high punitive effect on lap time.

The end of straight (EOS) speed at Sepang was 301kp/h in 2008. Sepang ranks as the 12th fastest EOS speed in the 2009 calendar, and this is one indicator of the wing level typically selected to optimise the downforce/drag ratio.

Pitlane & refuelling strategy

The pitlane length and profile (i.e. corners in the pitlane entry) contribute to the determination of the optimum fuel strategy. The pitlane loss at Sepang is approximately 22 seconds, the 5th most penalising pitlane in the Championship. To complete a normalised distance of 5km around the Sepang circuit requires 2.38kg of fuel against an average of 2.42kg per 5km across all circuits this season, making the circuit the 5th least demanding track of the year in terms of fuel consumption.

Safety car

Another key contributor to the determination of race strategy is the likelihood of safety car deployments, which are influenced by weather considerations, the availability of clear run-off areas that allow racing to continue while recovery takes place and the circuit profile, especially the character of the entry and exit into turn one at the start of the race. Since 2002, there have been no safety car deployments in Sepang, making it statistically unlikely that the circuit character, based on historic data, will induce safety car periods.

Temperature, pressure & humidity

It is a long observed tradition that drivers arriving at Interlagos complain about a lack of grip and an absence of engine power. Having become acquainted with a baseline of engine and aerodynamic performance during the season, the climb to 750 metres above sea level for one of the final races can, courtesy of the reduction in air density, rob a Formula One car of engine power, aerodynamic performance and cooling. The losses can come close to double digit percentages and thus have a very real impact on car performance. Air density is a factor of the prevailing ambient temperature, which varies most significantly by season, air pressure which is closely linked to altitude and, to a much smaller degree, by humidity. Thus if races are run at the same time each year, the factor that tends to have the greatest bearing on air density is elevation. Sepang is 40m above sea level and has an average pressure (1004.41 mbar) when compared to other races venue in the 2009 Championship. As a consequence, the circuit's ambient characteristics will be average for engine performance across all tracks visited during the season.

-credit: williams