IMSA Sports Car Test Reveals New Storylines Ahead of the Rolex 24 at Daytona

Aston Martin/Drew Gibson

It was testing time again for the IMSA WeatherTech SportsCar Championship cars last weekend at Daytona International Speedway, in preparation for January’s Rolex 24 at Daytona season opener.

“We have 31 cars, but that’s no reflection on what we’re going to see in the Rolex 24. It’s half of what you’ll see in total car count,” said John Doonan, IMSA president. Demand for a starting spot in the 24 is so great that it’s expected that some entries won’t make the grid.

This test marks a quick turnaround from the last race of the 2024 calendar, the Petit Le Mans at Michelin Raceway Road Atlanta on October 12th: “As you know, there’s no off-season—just a post-season and immediately a pre-season.”

That said, there was news made at the test, sometimes by new models, sometimes by changes in the different teams from last year.

The GT cars—those are the racers that begin life as real cars, such as the Porsche 911 and Ford Mustang—were there for a specific test: Trying out the new torque sensors, “which we’ve run in the GTP cars for the last two years. It’s an incredible tool, and it will help the sanctioning body, and all the manufacturers,” Doonan said.

John Doonan IMSA President
John DoonanCourtesy IMSA

The torque sensor, located on the drive axle, “is measuring, at the simplest definition, the torque at the wheels. That gives us a tremendous real-time read on the power the car is making. In the format that we race—multi-class, multi-manufacturers, multi-platform, front-engine, rear-engine, turbo and non-turbo—it’s a tremendous tool for us to use on the ‘Balance of Performance’ measurements.”

Given the variety of the cars being measured, Balance of Performance, or BOP, is an ever-changing strategy that IMSA uses to ensure a level playing field. A car going too fast for its class can be BOP-ed with extra weight, a smaller gas tank requiring more frequent pit stops, adjustments to aero components or horsepower itself. A car that needs more help to be competitive would get the opposite.

IMSA competitors have been notorious over the years for “sandbagging,” or not going as fast as they are capable of, especially in these pre-season tests and in qualifying, for fear of being slowed down by new BOP rules.

Doonan doesn’t think that’s the case so much now, but he admits he could be a bit naïve. “For me, our sport is about demonstrating our best performance, and the drivers behind the wheel, the men and women in the pits, and the manufacturers are here to demonstrate their capabilities. With the torque sensors, they actually tell us the capability. In a multi-platform class, you want to put on the best show with everybody having a shot. I think in terms of sandbagging, the torque sensors are one additional and new tool that eliminates that, because we can see what kind of power the car is making. We have over 200 sensors on the car providing us real-time feedback.”

So what else was new at the test? A dozen of the 31 cars in attendance were the fastest class, GTP, with the biggest news made by the presence of the new Aston Martin GTP car, a racing version of the road-going Valkyrie supercar. The company hasn’t yet decided whether or not it will debut at the Rolex 24, with this test playing a major role in that final decision. The Aston, fielded by the veteran Heart of Racing team, is powered by a V-12.

“Aston has been a great partner, a multi-time champion on the GT side. With 19 manufacturers participating in IMSA this year, we have a lot of premium brands, and Aston being one of them, so to see that car in the top category, after all the success in GT, it’s amazing. And to hear it—the V-12 makes a magical sound, and that’s another element of the variety that we have,” Doonan told us. “You’ve got a ground-pounding V-8 in the Cadillac, the sweet sound of an Acura and a BMW and a Porsche, all turbocharged V-8s, then of course the Lamborghini’s twin-turbo V-8, but what the Aston brings to me is this sound that appeals to those of us who’ve been around the sport for a long time. We’ve heard that noise, and now it’s coming back.”

As expected in a first outing, the Aston Martin was at least a second slower than the faster GTPs, but reliability seemed reasonably good. The final driver lineup has not been announced, with Aston’s GT drivers—Alex Riberas, Ross Gunn and Roman De Angelis—handling the Valkyrie test.

IMSA-Aston-Martin-GTP cockpit
YouTube/IMSA Official

In other news, Meyer Shank Racing returned to GTP after a year off, again with Acura. The Acuras were the quickest in three of the five test sessions, with drivers Tom Blomqvist and Nick Yelloly setting fast times, both in separate cars. “Everything’s gone smoothly,” Yelloly said. “Lap time-wise, it’s always nice to see yourself further at the front, but it doesn’t matter until we go racing, to be honest.”

With Chip Ganassi leaving IMSA after multiple seasons with Cadillac—one rumor suggests he may be helming the future Genesis GTP program—the brand will be raced by Wayne Taylor, with two cars, and Action Express with one.

In GT3—with the classes being GT and GT Pro—the Ford Mustangs topped the timesheet for both, with Dennis Olsen fastest overall. The Mustangs were followed by a Porsche 911, then a Lexus RC F. The Mustangs were so dominant that it would likely be a surprise if they don’t land on the BOP list for 2025.

There is one more test before the Rolex 24: The Roar Before the 24 is scheduled for January 17-19, and unlike last weekend’s test, it’s open to the public. The Rolex 24 takes place the following weekend, with the four-hour IMSA Michelin Pilot Challenge race running Friday, January 24, and the Rolex 24 running the weekend of January 25-26. More information is available at IMSA.com.

Read next Up next: History Repeats Itself: TWR Returns with a Jaguar XJ-S Ready for the Road and the Track

Comments

    Sounds like a nice bit of kit provided the goal is to keep the cars on something of an even playing field. However IMSA has in the past has jumped to conclusions after The 24. Giving and taking based on the results of one race. Some tracks may favor one car over another while at another it may be the other way around. So, for simple example, while one team may emphasize straight away speed another might sacrifice that in favor of handling. How many times have you heard ‘ this track does, or doesn’t, play to our strengths .That choice in creating a car that is the right balance and fit is a strategy that should be left to the teams. IMSA seems to sometimes ignore that and change the rules without appropriate consideration. They can’t seem to take a wait and see approach and leave well enough alone until after the next race.

    What some miss here is the Balance Of Power changes other through the season. It has to as what shows up at Daytona can change much due to sand bagging and the fact team often start with new cars and they get faster as they develop. The cars that start the season often have changed much by the last race.

    While BOP is not fun it is all that keeps the series alive. If not one team can out spend and drive up cost to where MFGs will leave. It has happened in a number of series. Even IMSA died at one point.

    Keeping cost viable is required.

    Please, please, run the V-12. And run it around the track near the Caddy V-8. The hybrid Fours & Sixes sound like appliances in comparison.

Leave a Reply

Your email address will not be published. Required fields are marked *

Your daily pit stop for automotive news.

Sign up to receive our Daily Driver newsletter

Subject to Hagerty's Privacy Policy and Terms of Conditions

Thanks for signing up.