The first indications may already have emerged during Friday’s opening practice session, where Acura Meyer Shank Racing laid down an early marker by topping the timesheets with both ARX-06s. The fastest Cadillac was over 1.2 seconds adrift in third, just ahead of the 2025-spec JDC-Miller Motorsports Porsche 963.
BMW M Team WRT and Porsche Penske Motorsport, meanwhile, conceded 1.380s and 1.587s respectively to the benchmark pace.
Before the green flag falls, here are the five biggest questions surrounding the 2026 IMSA SportsCar Race.
Can Porsche Penske honour its history?
Ever since back-to-back victories at the 24 Hours of Daytona and the 12 Hours of Sebring, Porsche Penske Motorsport has managed just a single podium finish in the last four races. Will that drought finally come to an end this weekend?
Nothing is guaranteed.
As has been the case throughout the previous four rounds, the Balance of Performance does little to favour the Porsche 963. The 2026-spec LMDh carries 13 kg, 21 kg and 36 kg more than the Cadillac, Acura and BMW respectively, while also running with less power.
“The race at Road America will be six hours long for the first time,” said Felipe Nasr. “Endurance races are our strength. We want to close the gap to the championship leaders and, if possible, get back to the top step of the podium.”
A victory would be particularly timely, as Porsche and Team Penske are celebrating their shared history with two one-off liveries. Car #6 pays tribute to the legendary 1973 Porsche 917/30, while the #7 echoes the colours of the Porsche RS Spyder that dominated the LMP2 class from 2005 to 2008.
Can BMW M Team WRT finally spin its web?
After claiming three consecutive podiums — including two victories — in the World Endurance Championship, BMW M Team WRT appears to have found its stride on the world stage. In IMSA, however, the German-Belgian operation is still chasing its maiden victory.
Does it already have what it takes? “Without a doubt,” LMDh Lead Engineer Adam Hardy told The Stint.
“We’ve been having good and bad weekends throughout the season so far this year,” Dries Vanthoor said.“Looking into last year, Road America can maybe bring us some luck and be the turning point in the season for us.”
Road America would certainly be an appropriate venue. It was here that the BMW M Hybrid V8 claimed its only IMSA victory to date, twelve months ago.
Adding to the occasion, the #24 BMW will race this weekend in a special Spider-Man: Brand New Day livery celebrating the release of the upcoming Marvel film.
Cadillac taking another step towards the title?
Six podium finishes in six races this season, added to the final two rounds of 2025, mean Cadillac heads to Road America on a remarkable run of eight consecutive GTP podiums.
Unsurprisingly, that consistency has made Jack Aitken the clear championship favourite. The Briton remains the only driver entered for every round of the season on the #31 V-Series.R. He is joined this weekend by Earl Bamber and Frederik Vesti aboard the AXR Cadillac.
Such is Cadillac’s advantage that, even if the #31 were to retire on the opening lap, Aitken would still leave Road America leading the Drivers’ Championship, while Action Express Racing would also retain the Teams’ lead.
With only three races remaining after this weekend, however, Road America could prove pivotal. If Cadillac’s rivals are to mount a late title challenge, this may be one of their last realistic opportunities to halt the #31’s momentum.
Robert Wickens returns to the Endurance Cup
Robert Wickens received a late call-up from DXDT Racing after Salih Yoluc withdrew due to a family emergency. The Canadian therefore shares the #36 Corvette Z06 GT3.R with Charlie Eastwood and Mason Filipi in the GTD category.
Having contested the sprint races at Long Beach and Canadian Tire Motorsport Park this season, Wickens now returns to IMSA endurance racing for the first time since the 2017 Daytona 24 Hours — the final endurance race of his career before the IndyCar accident at Pocono in 2018 that ultimately led him to develop the hand-control system he uses today.
It represents another important step in his remarkable comeback, as Wickens continues to make no secret of his ambition to contest a full IMSA campaign in the near future.
Road America embraces its endurance heritage once again
As the Wisconsin circuit celebrates its 70th anniversary, Road America returns to a format deeply rooted in its own history.
When the venue staged one of its first major events in September 1956, the Road America National Endurathon was already contested over six hours.
Won by John Kilbourn and Howard Hively in a Ferrari 375 MM, that race inspired the creation of the legendary Road America 500 the following year, widely regarded as the first 500-mile sports car race in history. Held until 1968, the event returned in 1979 under the IMSA Camel GT banner before evolving into several different formats over the following decades.
“It’s no secret that I have a personal passion for Road America. When I was growing up, it hosted a 500-mile race for decades,” IMSA President John Doonan said when the 2026 calendar was unveiled.
“What you’re seeing is something fresh and exciting for the fans, while also demonstrating the flexibility of our promoter partners who were willing to shake things up a little.”
“Road America has the infrastructure, and my hope is that a six-hour race will allow us to pack the place even more than we have over the last few years.”
Having been limited to a 2h40 sprint since returning to the IMSA calendar in 2014, Road America now joins the Michelin Endurance Cup for the first time with a six-hour race.