Nigel Dobbie: The Balance of Power at Le Mans 2013
The FIA / ACO have a number of ways of balancing the performance of the different cars in the different classes competing at Le Mans. Usually the cars run to a standard minimum weight, have a standard rear wing height relative to the height of the roof of the car, and are fitted with standard air restrictors for the engine breathing.
The test day two weeks before the race and qualifying indicated that this year, for whatever reason, the ACO / FIA had got the balance badly wrong for both GT classes.
How did all this affect the cars at Le Mans in 2013? Well, the two Pratt & Miller-prepared Corvette Racing Team C6R-GT cars were running the same restrictors as last year (27.9mm), the chassis had some minor improvements, the aerodynamics had been improved slightly, and yet the cars were slower than last year and significantly slower than most of the other cars in the field except for the SRT Vipers.
The Aston Martin, despite setting the pole time for the GT PRO class in 2012, was further aided with a weight reduction, bigger fuel tank capacity, and 28.3mm restrictors. The brand new Porsche was given massive 28.6mm restrictors and a 35kg (77 pound) weight break – i.e. the car was allowed to run lighter than the 1245kg class standard weight.
When a manufacturer introduces a new car is it usual for the ACO / FIA to err on the side of caution and penalize the car, in case it turns up and wins straight away. As Porsche was celebrating 50 years of the 911 and Aston 100 years as a company, this could be the reason this normal protocol was being ignored. The test day two weeks before the race and qualifying indicated that this year, for whatever reason, the ACO / FIA had got the balance badly wrong for both GT classes.
All The Cards On The Table
In practice for the GT Pro Class, the Aston Martin ran a best lap of 3:58.8; the best Porsche time was 3:59.4, the best Corvette also a 3:59.4, the best Ferrari a 4:00.4 and the best SRT Viper a 4:01.7. When it came to the qualifying before the race, things changed significantly with the best lap from an Aston Martin of 3:54.6 (4.2 seconds faster), Porsche 3:55.6 (2.8), Ferrari 3:55.9 (4.5), Corvette 3:58.6 (0.8) and SRT Viper 4:00.8 (0.9).
In the GT Amateur Class at the test day, the Aston Martin ran a best lap of 4:00.8. The best Porsche time was a 4.04.0, the best Corvette a 4:06.7 and the best Ferrari a 4:07.7; for qualifying, Aston Martin ran a 3:57.7 (3.1 secondss faster), Porsche 3:58.8 (5.2), Ferrari 3:59.9 (7.8) and Corvette 4:04.5 (2.2). This also showed that the Amateur Class Aston Martin and Porsche entries were actually faster than the Professional Class Corvettes, and would start ahead of them on the grid.
The general concensus of those people from the Corvette Racing team I spoke to was the GM prepared-motors in the Corvettes were not making enough power and torque where it is needed – the cars were desperately slow out of the corners compared to last year. The improvements to the Aston and the new Porsche mean it was obvious that the Corvette would struggle this year at Le Mans, and so it proved.
Due to the massive number of full course yellows and the amount of time run behind the safety cars, the Corvettes were actually a lot closer in terms of distance and time from the class-winning Porsches than I had predicted. I had calculated that the four seconds a lap times approximately 15 laps per hour multiplied by 24 hours would have amounted to 24 minutes, or about 6 laps down by the end of the race.
The best race lap times during the race were set by Pro Aston Martin 3:54.6 (same as their qualifying time) while the Amateur Class Aston managed a best lap of 3:59.0. The Pro Porsche ran 3:55.3 (Amateur 3:57.9), Pro Ferrari had a 3:56.3 (Amateur 3:57.4), and Pro Corvette’s best was 3:57.0 (Amateur 4:01.1).
Corvettes finished up 4th and 7th in the GT Pro class, with the #73 crew of Jan Magnussen, Antonio Garcia and Jordan Taylor leapfrogging up to 4th place after a ballsy call to stay out on slicks in torrential rain and the subsequent safety car proving it was a tactical masterstroke. The #73 still finished the race 3 laps behind the class winning Porsche.
The #74 Corvette had to pit in the final hour for an exhaust problem which could potentially have caused a fire, so the team took the sensible option given the bigger picture, i.e. no chance of winning at Le Mans and an ALMS title to defend, and sat in the pits, only taking the car out for the final lap so that the car was classified. It finished 6 laps down on the class winning Porsche.
What Lies Ahead?
In fairness to the ACO / FIA, the balance of performance is a hugely difficult task, and all of the manufacturers will do whatever they can to make it appear their car is slower before the race. This year the ACO / FIA got it badly wrong. I think everyone accepts this – I just hope that they do too, and work to bring the balance back. I really hope next year with the introduction of the C7R that the ACO / FIA are as generous to the new Corvette as they were to Porsche and Aston Martin this year.