No manufacturer was without learnings and teething issues, which created one of the most intense title bouts in recent memory.
Each of them – Acura, BMW, Cadillac and Porsche – reached victory lane at least once. Additionally, only 98 points separated manufacturer titlist Cadillac from BMW in fourth.
There was significant growth across all four makes in the first year of the hybrid, which is a Bosch-supplied motor generator unit that powers both the Williams Advanced Engineering battery and the car itself via an Xtrac gearbox.
When asked by Motorsport.com about how close or far off the maximum potential of this particular GTP car is, representatives of all four manufacturers weighed in.
Maurizio Leschiutta, the project leader for the BMW M Hybrid V8, was the first to provide feedback and noted some of the development was aided by experience learned from its involvement in Formula E.
“I guess you don't know how far are you away from your target until you know where your target is,” Leschiutta said. “Today, to say that we know the ultimate potential of this car, I don't think we do. We're still on a very steep part of the learning curve because it is a complex car.
“We have experience with electrical powertrains with our Formula E group, so we have some know-how there, and trying to understand how to make a car like this feel natural in the hands of a driver. Also, the drivers have to get used to cars like these because they are perhaps different than what they're used to driving.
“I don't think we've explored the full potential, for sure. We'll continue to see people making gains. Now, they won't be such big gains as perhaps we saw from last year to this year, but we'll continue to make gains and get better and better.”
Urs Kuratle, Director of Factory Racing LMDh at Porsche, believes the learning curve will flatten out but expressed some of the details being related to the Balance of Power.
“We would love to know what our potential is and also would love to know what the others potential is,” Kuratle said.
“I know also obviously that the governance would also like to know how far do they go, because that's a BoP (Balance of Power) related question as well.”
While continued development equals progress, Kuratle also believes the majority of gains will come from software.
“I do believe that the biggest chunk of potential from now on is probably on the software side in various different areas,” Kuratle said.
“But the hardware is probably the first one you can get solved. Hardware is probably the first one you get used to, including the drivers and everybody. But yeah, sure, there is still some potential.
“We don't know how far it goes in our case, and obviously not in the other cases, but I do believe that the biggest chunk is in software. Not saying there's no potential in the other areas, but the biggest part probably is software from now on.”
Similarly, Mark Stielow, the Motorsport Competition Engineering Director for General Motors, shared any improvements to be made would likely be marginal in comparison to this past season.
“As engineers move down the Pareto chart, you get the big items and then once we started getting the car durable and reliable, then we started trying to keep on nicking away at it,” Stielow said.
“The gains are going to be smaller and smaller. “This year, 2023, we found the biggest gains and as we learned more about the car and learn more about the platform and able to dig farther down on the Pareto chart of things to work on, we will find some more speed in the car. But everybody does. We've been rubbing on a lot of these things, like on the IndyCar side, for 10 years. So, we keep on making 'em faster, but it's the same recipe. We've got a long ways to go yet. But in general, we're still grinding on things and software's going to be a big opportunity."
David Salters, President Honda Racing Corporation US, closed out the roundtable of thoughts by suggesting some of the potential advancements haven’t even become an idea to put to paper yet.
“I'm sure there's chassis stuff that we don't fully understand,” Salters said. “Tires - people work on them forever - and then there's powertrain stuff and software and things that we probably haven't thought of yet. I'm sure it's less gain than it has been because it was a new car and we've raced it quite a lot now.
“So, it will be less, but this, this business - any sport - is about the accumulation of marginal gains. You look across all the bits and you see what you can add up, and that's why we get up in the morning.”