IMSA will welcome a new breed of LMDh machines from Cadillac, Acura, Porsche and BMW in the renamed GTP class next year, marking the beginning of a new golden age of sports car racing.
While based on LMP2 cars like their DPi predecessors, the LMDh machine is much more complex and also features a special hybrid system jointly designed by Bosch, Williams Advanced Engineering and Xtrac.
All four manufacturers have run into problems in testing so far, particularly with how the hybrid system is integrated with the rest of the powertrain as they race to get their new cars ready for the 24 Hours of Daytona on 28-28. January 29.
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With the IMSA-approved test taking place in early December and the start of the season itself being less than two months away, time is running out to resolve any issues.
Chip Ganassi’s Bourdais is pleased with Cadillac’s preparations for 2023 so far, but is aware of the role reliability could play in the season opener after seeing rival manufacturers experience technical issues during last month’s combined Sebring test.
“From what we’ve gathered, Porsche still seems to have some hybrid issues,” the 2014 Daytona winner in an Action Express Racing Chevrolet DP told Autosport.
“I don’t know if it’s vibration related or anything because we really haven’t had any.
“BMW certainly had a lot of problems when we did that 24-hour simulation test. They stood still for a long time and came out again and broke down again. They then came back out, ran for an hour, packed up the whole thing and went home.
Bourdais expects reliability to be the deciding factor at Daytona
Photo by: JEP/Motorsport Images
“So I think we all know that reliability is going to be the factor of who ultimately wins in Daytona. Acura also had a problem.
“If you can run a decent race and have no major problems, you are probably in a very good place. I hope we will be the ones.
“All we do is focus on ourselves and try to have a car that is fast and reliable. We don’t really know how fast, but at least we can immediately achieve the reliability that goes to a 24-hour race.
“It’s always a huge test at Daytona. When there’s a rule change like this, it’s the car’s first race, it’s a 24-hour race and it’s January.”
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While some IMSA manufacturers have experience using hybrid systems and electrical components from their previous racing programs, they are now required to source the engine, battery and gearbox from designated suppliers.
While some of the issues they encountered during testing had to do with the components themselves, the integration of the hybrid system with the rest of the powertrain was also a headache – and some manufacturers have outperformed the rest in this area.
Bourdais feels the challenge of making the powertrain reliable is made even more complicated by the fact that there are a number of suppliers involved, rather than one manufacturer building everything in-house under one roof.
“It’s not that bad, but the system is certainly complex and there are a lot of people involved,” he explained.
Bourdais to run a Chip Ganassi-run Cadillac in IMSA next year, but integration of hybrid systems poses new challenges
Photo by: Andreas Beil
“You have the people from Bosch, the people from Williams, this and that, integrating all that into the engine and drive system that is different for everyone.
“It’s extra challenging because not only you and your system manage everything, you have to get changes from Bosch.
“Obviously they have been very helpful, but they are also trying to figure out their systems themselves and make sure there are no side effects from whatever the regener is doing and how you forcefully did it.
“The system isn’t small, of course, the battery is quite big, so integrating everything and making it work with all your systems is a few extra steps that you have to get used to and do well. So we are still working on this side.”