Michelin IMSA Insider: Spotlight Shines at Lime Rock

Two times a year, the IMSA spotlight shifts from the headline-grabbing prototypes to the heart and soul of sports car racing, as the IMSA WeatherTech SportsCar Championship GTD and GTD Pro classes fight for the overall race win at Lime Rock Park.

GTD entries have taken top GT honors from their Pro twins three times already this season, at Daytona (No. 27 Heart of Racing Aston Martin Vantage GT3), Laguna Seca (No. 91 Kellymoss with Riley Porsche 911 GT3 R), and Watkins Glen (No. 12 Vasser Sullivan Lexus RC F GT3).

Still, the GTD Pro lineup appears formidable with Corvette Racing, winners of the most recent IMSA round at Canadian Tire Motorsport Park, joined by the defending Northeast Grand Prix winning Pfaff Porsche team, the Pro side entries from Heart of Racing Aston Martin, and Vasser Sullivan Lexus, plus the powerful WeatherTech Mercedes-AMG team.

Pros versus Pros

The GTD formula for overall wins typically sees the lower-rated GTD driver start and turn the car over to the Pro co-driver near mid-race.

At that point, the race is straight up, pros versus pros in identical class cars and Michelin Pilot Sport S9M commercially available race tires. The only difference is in the class color coding, red for Pro, green for GTD.

With 15 of the 20 WeatherTech GT entries, including top Acura, Aston Martin, BMW, Lamborghini, Lexus, McLaren, Mercedes AMG, and Porsche, the GTD cars will certainly be in the mix for the overall win here at Lime Rock.

After all, the only thing better than winning the GTD class would be beating all the Pros and being the overall race winners.

A TCR Pilot Challenge Overall Winner

Lime Rock presents a first-ever opportunity for the front-wheel drive TCR entries from Alfa Romeo, Audi, Honda, and Hyundai to have their own celebration, as their bigger, Grand Sport (GS) compatriots made a one-off appearance in Detroit and have cleared the stage for a TCR overall Michelin Pilot Challenge win.

The quick and nimble TCR cars have been closing on the GS field, especially at Lime Rock Park where the 1.474-mile circuit puts a premium on handling.

Since Michelin’s debut as the official tire of IMSA in 2019, the TCR lap record at Lime Rock has been lowered by nearly 2.2 seconds, a 3.95 percent improvement in just three races.

The TCR lap record is now less than half a second (0.47s) off the GS record. In 2019, the TCR top qualifier ranked second overall and in 2021 third, just one-tenth off the GS pole time.

So, while this week someone will become the first TCR overall winner in Pilot Challenge competition, what the feisty front wheelers really want is the next step – an overall race victory over the GS field in a Michelin Pilot Challenge race.