IMSA has introduced a revised Balance of Performance process that’s aimed to “put structure” into its existing system, while delivering greater transparency to manufacturers.
Rolled out during last weekend’s Roar Before the Rolex 24, a greater focus on data has been utilized in the streamlined process, which according to Geoff Carter, IMSA’s senior director of technical regulations and compliance, has come with the full approval by all manufacturers.
The changes, to be utilized in the DPi, GTLM and GTD classes, are focused on manufacturer-supplied data that’s turned into ‘weighted eclectic lap times’ for each car at each track.
Carter said manufacturers must now supply its car’s sensitivities to 10kg of weight and 7.5 kW of power for each sector of each track, with an average formulated and taken into account for the BoP.
A BoP adjustment based on a two-race rolling average will be implemented if a car is outside of the defined performance window, with a maximum change of 20kg and +/- 3 percent of power permitted per race.
“This is the structure that all the manufacturers agreed to and we’re going to try that,” Carter told Sportscar365.
“It’s an evolution to our process. What we’re doing is putting more understandable structure in place. Now it’s pretty straight forward. ‘Here are the thresholds, magnitudes and frequencies.’
“We’re trying to take some of the pressure off the technical committee by having some delineated structure and to give some more transparency and understanding to the manufacturers for the consistency of how it’s going to go.”
Carter said the aim is to have fewer BoP changes throughout the season, although maintaining a structured system that still allows for human oversight.
It’s understood none of the IMSA manufacturers were in favor of a fully automated BoP system, similar to what’s used in the FIA World Endurance Championship’s GTE-Pro class.
Event-Specific BoP for Daytona
Another change for 2019 is that the Rolex 24 at Daytona will be an event-specific BoP across all three classes, with data from regular season races not taken into account.
IMSA had based last year’s Daytona BoP on its end-of-2017 data, in what Carter said came with mixed results.
“We came up with our starting BoP for the Roar based on the corrected 2018 post-race analysis from the Rolex 24, using the agreed upon sensitivities,” he said.
Sebring will essentially be “ground zero” in the new BoP process, according to Carter.
“We want to make [the system] better,” he said. “Our fans, our manufacturers, our competitors, they all deserve better racing.
“Myself, Simon [Hodgson, IMSA VP of Competition] and the whole technical committee, we sit around and say how we can make it better. The only way you figure out how to make it better is to be self critical of where we were deficient.”