IMSA takes North American sports cars into hybrid era

DAYTONA BEACH, Fla. (AP) — The Cadillac growls, while the Porsche and BMW scream. The Acura sounds like an Indy car, and for fun, turn your back to the track and listen carefully as the cars roar around Daytona International Speedway in a new era of IMSA sports car racing.

The top prototype class has switched to hybrid engines this year to make IMSA the first North American racing series to make the technology upgrade. It was the automakers that wanted to move to hybrid so that their motorsports programs would reflect the direction most have taken for their road cars.

“We are in the transformation, or transition, into the electric world,” said Andreas Roos, head of BMW M Motorsport. “This is the perfect fit to be in parallel between our road car development and our racing. It's very important that we have a road-car relevance and this is a perfect match.”

The cars make their debut Saturday in the twice-round-the-clock Rolex 24 at Daytona, which has been described as a "symphony of sounds" because of the new engines. The hybrid powertrains marry a traditional internal combustion engine with Bosch’s Motor Generation Unit, an energy recovery system that includes batteries and an Xtrac gearbox.

One of the major concerns headed into this new era was that the hybrid technology would rob the cars of the loud roar that is part of motorsports' allure. But the opposite has happened as the four manufacturers in GTP — double the number from last year — created engines with distinctive sounds. BMW and Porsche both moved up classes to be part of the endeavor, and Lamborghini has announced plans to enter the series.

“The thing I like about the hybrid system versus strictly (electric) is we still have a nice sound, and I think that's very important. They all sound good, like an orchestra playing out there,” said NASCAR chairman Jim France, who also owns IMSA. “I think the formula that we have is going to be very important for motorsports.”

The new rules package also makes IMSA's top GTP class eligible to race at the 24 Hours of Le Mans as early as this year. Acura and BMW have already said they won't be ready for Le Mans this year.

The changes have also lured Roger Penske back to sports car racing. Rahal Letterman Lanigan moved its BMW program up to IMSA's top class, and Michael Andretti last month partnered with Wayne Taylor Racing to get Andretti Autosport onto the grid.

The excitement has Daytona officials predicting the largest crowd in at least a decade for the 61st running of North America's most prestigious endurance race.