The IMSA WeatherTech Championship 2023 kicks off next week with the Rolex 24 at Daytona and with it a new generation of GTP hybrid prototypes. Between Cadillac, porsche, Acura and BMW carThere are a lot of changes to be excited about in the top tier, but one difference that might surprise you on race day is the sound coming from the pits.
Sure, the single-seaters and lower-class GT cars still have full internal combustion powertrains, but when a GTP machine takes off from its stall, it won’t contribute much to the hum. . Instantaneous torque from the electric motors means all you’ll hear is a groan that gets louder and louder until the petrol engine plunges straight into the pit. Or not.
If you want a preview of what we’re working on, racer Marshall Pruett just posted a short video where you can see Cadillac, Acura and BMW in premiere form. As Pruett explains, teams are free to use any type of propulsion they like, whether it’s shutting down battery power and quickly switching to ICE once the speed limit is reached, or just going on electricity.
The three-second time limit was originally set for maximum electrical power, but IMSA decided to drop the limit out of concern for motorists getting stuck on their way back to the track. On the other hand, the automatic ignition system, which is tasked with starting the engine as soon as the car plunges out of the jack, has been banned by 2023.
All GTP chassis have the same energy recovery system using parts from Bosch, Xtrac and Williams Advanced Engineering, but they are fitted with different engines developed independently by each manufacturer. Acura touts a V6 engine, while the rest use a V8 and only the Cadillac is naturally aspirated.
Mandating a spec hybrid unit helps to keep costs down while still offering manufacturers the opportunity to flex their muscle and differentiate their machines on the ICE side. It’s certainly a new realm for IMSA, but one that holds a lot of promise, with more automaker involvement at the top level than we’ve seen in ages.
Initial practice for Daytona was held Friday, with racer Report top three times posted by Acura, then Porsche, then Acura again. Of the nine cars in the class, six overtook the leader within a second. Next weekend can’t come early enough.