Although Corvette Racing's championship-winning C6.R hasn't turned a wheel at the new Miller Motorsports Park, Chevrolet's factory team has already completed hundreds of virtual laps around the 4.5-mile circuit in an effort to gain an advantage over its rivals.
With Aston Martin, in particular, appearing to be a threat to Corvette's previous superiority, the US marque has employed sophisticated computer simulation software to give its team a headstart on setting up the C6.Rs for the inaugural Utah Grand Prix, the next stop on the American Le Mans Schedule, this weekend [15 July].
"The laptime simulation software we use is a proprietary programme that is constantly evolving," explained Steve Cole, race engineer for the #4 Compuware Corvette of Oliver Gavin and Olivier Beretta, "We compare and correlate the predictions with 'real world' results as we develop the software. The simulations give the team the ability to evaluate various set-ups in the computer before the cars go to the track."
That foresight could prove to be a crucial advantage for Corvette Racing in the fifth round of ten this season. The Utah Grand Prix will be the first major auto race contested on the new 23-turn road course, and the team will not only have to contend with the effects of altitude at the track's 4923-foot elevation, but also the effects of 'balance of performance' adjustments that have tilted the playing field in the GT1 class, based on round four's results at Lime Rock Park, towards Aston Martin.
"We start with what we think is a reasonable chassis set-up with springs, sway bars, dampers and so on," Cole continued, "Then we run lap simulations on the computer, adjusting the gearing, the weight distribution and other items until we come up with a set-up that gives an optimised performance target.
"There are challenges we deal with in this process due to limited information about the new surface, so you have to make some assumptions about the grip," he noted. "Surface friction, bumps, banking and grade are all unknowns at this point for the new Utah track. Beyond this, the track characteristics change over the course of a race weekend as rubber builds up on the racing line, but the simulation programme gives us a solid starting point for the set-up. We can then refine that based on driver feedback and track data."
The thin air of the Salt Lake Valley will affect both men and machine, with Cole estimating a 14 per cent loss in engine horsepower compared to racing at sea level.
"The air is less dense, so we won't have as much aerodynamic downforce and cooling," he revealed, "Fortunately, the Corvette C6.Rs have plenty of cooling capacity, so the heat shouldn't create a problem."
The effects of altitude on the Corvettes' engine performance will be magnified by smaller intake restrictors that were mandated by the sanctioning body to balance competition in the GT1 class. The Corvette LS7.R engine's new 30.8mm restrictors represent a six per cent reduction in area from the 31.8mm restrictors used previously, producing a corresponding decrease in engine output. In addition, the Corvette's fuel capacity has been reduced from 100 litres to 90 litres, with both performance adjustments set to be in effect for the remainder of the season.
