How do you make an already race-winning car like the Lexus RC F GT3 in the IMSA WeatherTech SportsCar Championship’s GT Daytona class even more competitive? After all, through its strict homologation processes and detailed Balance of Performance regulations, the GTD class seeks to create parity among a wide variety of competing cars. But it’s a question that Vasser Sullivan race engineer Geoff Fickling grapples with on a daily basis.
“Because we have such a solid racecar, we just need to find the sweet spot to run it in the right range at each circuit we go to,” says Fickling. “Say the car is running too high [of a ride height], that can lead to a loss of aero efficiency and increase tire degradation, which all amounts to a loss of performance.”
But nothing in racing is ever straightforward. Fickling and the Vasser Sullivan engineering crew, along with the team’s drivers, go through a methodical list of areas on the RC F GT3 that can influence its performance. Static and dynamic ride height, downforce settings, springs, roll bars, and tire camber angles form the basis of inquiry and discovery. Within each of these, the changes they’ll dial in to optimize performance can come down to the smallest of percentages, akin to shaping wood with 1000-grit sandpaper, one pass at a time.
“We go into every session with a plan down to how many laps we will run and what questions we need to answer with each lap,” explains Fickling. “Following the session, we’re looking at the data from every angle, looking for trends that will give us a clue on where to go with the adjustments.”
Because the series has enjoyed a stable schedule over recent years, the tracks, along with the car, are mostly a known quantity. That leaves atmospheric conditions, which can vary considerably from one day to the next, or even one session to the next, as the most influential variable in how to set the car up for the race.
“As race engineers, the biggest challenge we have is if the conditions on race day are completely different to what we had during practice,” says Fickling.
“But it’s also an opportunity, because if we can dial in our car using all of the accumulated data and experience we have, then we can get a leg up on the competition. In the end, what we are really looking to do isn’t to ‘improve’ the car, so much as optimize it for the specific conditions we’re facing.”
Change of Plan…
If it’s engineer Geoff Fickling’s task to give his drivers the optimum car for the conditions, it’s the guy behind the wheel’s job to make the most of it. Yet those conditions are more than likely always changing.
And even if the weather is stable, other unpredictable elements, such as traffic, debris, or caution periods, can lay waste to the most meticulous pre-race strategies. As such, the drivers have a few tools at their fingertips to make changes that can bring the car back into its optimum performance window.
“From the cockpit we can change brake bias, traction control and ABS settings,” explains Aaron Telitz, who shares driving duties in the No. 14 Vasser Sullivan Lexus RC F GT3 with Jack Hawksworth. “The changes we make during a race or practice session are always up to the driver and never planned in advance. It’s more about what a driver feels they need to get the most from the car in that moment.”
Telitz adds that the dialog he and Hawksworth have with race engineer Fickling, in terms of how they relay what the car is doing out on the race track, is crucial. The more accurate their information, the more valuable it is in helping get the most out of their RC F GT3.