The extension of the lifespan of the GTP category in the IMSA SportsCar Championship could pave the way for new manufacturers to join, series boss John Doonan believes.
Doonan reiterated IMSA’s position that there is interest from major car makers to join the top class of the series in the wake of the announcement ahead of this month’s Le Mans 24 Hours that the LMDh and Le Mans Hypercar rulesets were being expanded through to the end of 2029 in both North America and the World Endurance Championship.
“I feel there is real interest; there are at least a couple [of manufacturers] who are seriously looking at the platform,” said Doonan.
“The [new] homologation gives stability for those who are here and opportunity for those researching entry.
“Now they know that if they came, for example, in 2026 they would have four years of competition with the same regulations.
“We’ve seen GTP racing in North America is mega and it is only going to grow.”
When pushed about likely new entries, Doonan replied: “More details to come.”
McLaren has again started talking publicly about its sportscar aspirations at the highest level following the announcement of the rules extension, while Alfa Romeo has long been known to have interest in the top category of IMSA.
Jean-Philippe Imparato, the CEO of the Italian brand that is part of the Stellantis group along with Peugeot, spoke openly about its WEC aspirations on the conclusion of its badging deal with the Sauber Formula 1 team at the end of last season.
The door is also open to the LMH manufacturers competing in the WEC's Hypercar class to join the IMSA series.
Aston Martin will be the first when it arrives next year with a solo Valkyrie AMR-LMH run on a factory basis by the Heart of Racing squad, which is also mounting a two-car WEC campaign.
“Aston has announced its intentions to come and we certainly welcome them as the first LMH manufacturer in IMSA competition,” Doonan said.
“We’d love to see some others join now that the time period has grown.”
Doonan stressed that room will be made for additional GTP cars beyond the 11 competing this year even though the IMSA grid is currently at capacity.
They would be “welcomed with open arms”, he said.
Additions next year will include the Aston and most likely an extra Cadillac when it is expected that Wayne Taylor Racing with Andretti moves over from Acura machinery to the General Motors brand to run a pair of V-Series.R LMDhs in place of Chip Ganassi Racing.
On Thursday, Honda Racing Corporation USA confirmed Meyer Shank Racing will return to its Acura programme for 2025.
Doonan also expressed a hope that one or more of the manufacturers currently competing in GTP will join Porsche in supplying cars to customers at some point during the extended life of the category.
Cadillac and Lamborghini have stated that they have no plans to release cars to customers and Acura has also suggested that it is unlikely, while BMW has so far left the door open.
The prospect of the existing manufacturers competing in GTP potentially revising the styling of their LMDh contenders was also raised by Doonan.
“Maybe there will be opportunity for styling upgrades - this will be up to the technical teams from IMSA and the FIA/Automobile Club de l’Ouest [which run the WEC],” he explained.
