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THIS TITLE stands for Auto Club de l’Ouest Balance of Performance. The ACO is the sanctioning organization of the Le Mans 24-hour endurance race, taking place as I write this. (At the moment, the race is in its fifth hour, not quite 7 p.m. Central European Time; approaching 10 a.m. in my southern California.)
Balance of Performance is the ACO’s and other sanctioning bodies’ means of leveling the race circuit for production cars of varying capabilities. Generally, the adjustments involve power, weight and fuel capacity. In particular, the ACO has performed more than a bit of balancing directly before the 2016 Le Mans among the five marques in its Le Mans GTE-Pro class, Aston Martin, Chevrolet, Ferrari, Ford and Porsche.
As described at caranddriver.com, as recently as yesterday the ACO and the Fédération Internationale de l’Automobile gave LMGTE-Pro entrants their latest BoP adjustments for the race. These are based on performance at previous events as well as testing and qualifying earlier this month at Le Mans. There are perhaps other inscrutable BoP criteria.
It reminds me of the Le Mans Index of Performance 60 years ago; of which more anon.
This year, the Chevrolet Corvette C7.Rs and Porsche 911 RSRs were initially given BoP handicaps based on earlier prowess. Then Ford GTs dominated qualifying with Ferrari 488 GTEs not far behind. Porsches were mid-runners; the Chevrolet Corvettes were at the bottom of the list.
Corvette and Porsche teams complained that the ACO was rigging a Ferrari/Ford shootout as in days of yore. Others said the ‘Vettes were sandbagging in qualifying, figuring that the ACO can make BoP adjustments right up to race time.
The ACO assigned Ford and Ferrari modest weight increases on Friday, extra ballast of 22 and 33 lbs., respectively. It also reduced Ford’s turbo boost at certain revs, worth perhaps a percent or two of output. Conversely, the normally aspirated Aston Martins and ‘Vettes got increases in their intake restrictor sizes, measured in tenths of a millimeter, but still significant.
How well does all this work?
At 1 a.m. Le Mans time, the eight top runners in LMGTE-Pro are Ford, Ferrari, Ford, Aston Martin, Porsche, Ford, Aston Martin and Corvette, all within two laps of each other.
I’d say that’s pretty good leveling of La Sarthe. Though radio commentators raise BoP issues, it’s no more suspect than the old days of the Le Mans Index of Performance. The idea of the ACO IoP was to reward a car of any engine size for exceeding by the highest percentage a predetermined minimum distance for its class.
Back in the 1950s, my anglophile motorsports upbringing taught me that the ACO’s IoP was merely a way to make sure a French car, typically of smaller engine displacement, won something. And, indeed, prize money for an Index of Performance victory was comparable to that of the overall winner.
To see whether there was proof of this over the years, I researched Le Mans Index of Performance of the post-World War II period, from 1949 through 1971, the IoP’s last year. There are several gaps; and, for a time, there was another award, the Index of Thermal Efficiency based on an entirely different calculation.
Over the 21 years that the ACO IoP was awarded, 9 1/2 had a French car win, the half being a 0.6-liter Monopole tied with an Aston Martin in 1950. Typically these French minis placed well down among finishers.
By contrast, 9 of the 21 wins involved non-Gallic competitors placing within the first five overall. Indeed, four of them were outright winners.
Written at 6:00 a.m. Pacific: During the last half-hour of the race, the ACO showed the Black/Orange flag to the 2nd-place Ferrari in LMGTE-Pro. The reason: Its side-identification light, used by scorers, was improperly lit (something that other cars had done during the previous 23 hours and 30 minutes).
A travesty of inconsistency. Up until now, my last line of this piece was “I doff mon chapeau to the ACO.” I have deleted it.
At 6:06 a.m., the Ferrari is shown on the official ACO website as having placed 2nd in class. Confusion reigns.
This overshadows the leading Toyota LMP1-H’s heart-breaking failure in the last three minutes of the 24 hours. Talk about drama!
© Dennis Simanaitis, SimanaitisSays.com, 2016