IMSA's Popularity Surges as Factory Teams Retreat

Sportscar racing is riding a wave of popularity, with IMSA's domestic audience up more than a third and international viewership up nearly a quarter last year. The series has leaned into streaming-friendly multi-class racing, open paddocks, and grid walks, drawing bigger crowds. IMSA President John Doonan said, "I think we're just scratching the surface."

But the business side is turbulent. Porsche halved its factory prototype program, keeping only its two IMSA cars, blaming a bet on an EV transition that hasn't materialized and tariffs on US-generated profits. Alpine is leaving the World Endurance Championship at year-end, with a Geely rescue looking unlikely, and Acura is ending its GTP program to focus on IndyCar.

The grid is not shrinking overall: Genesis has entered WEC, and Ford and McLaren join next year. The choice of LMDh rules by all three factory efforts reflects cost discipline—common hybrid systems and approved chassis—versus Hypercar's greater technical freedom and expense. With performance balanced anyway, the article suggests the extra cost may not be worth it.