Michelin Lime Rock Notebook

Clean and Green

The last three IMSA WeatherTech SportsCar Championship races at Lime Rock Park have produced only one full course caution period for just four minutes in 2018. The 2017 and 2019 Lime Rock WeatherTech events both ran caution-free.

Ultra-Close

The caution-free 2019 Lime Rock race produced one of the closest finishes in IMSA series history.

After 178 laps, the GTD class was decided by just 0.010 seconds as the Pfaff Motorsports Porsche 911 GT3 R of Dennis Olsen and Zach Robichon edged out the Meyer Shank Racing Acura NSX GT3 Evo of Mario Farnbacher and Trent Hindman.

Whether the Weather

That 2019 race saw temperatures reach 98 degrees ambient and 117 degrees on track. Preliminary forecasts for this week call for temperatures in the high 80s on Friday.

Saturday’s forecast is a bit cooler, with temperatures in the high 70s, but with a chance for thunderstorms.

Wait a Second

Horse racing railbirds say that there are horses for courses. If true, the Lime Rock Park 120 for the IMSA Michelin Pilot Challenge should be especially interesting.

While the IMSA GS class entries have approximately 400-450 horsepower compared to the 300-350 horsepower for TCR entries, the short straightaways at Lime Rock neutralize much of that power advantage.

While GS cars have a top speed in the 160 miles per hour range, the fastest GS top speed at Lime Rock in 2019 was 138.5 mph compared to a 134.4 mph in the TCR class.

The best GS lap was 54.446 seconds while the top TCR lap was 55.025 seconds.

Weighing In

The IMSA GS cars are generally heavier than their TCR counterparts, but there is one more twist to the form book.

The lightest GS car at the recent Watkins Glen race was the Porsche 718 Cayman GT4 CS MR at 2,866 pounds, just 12 pounds more than the Alfa Romeo TCR entry.

The heaviest TCR cars at WGI were the Hyundai Elantra N TCR and Veloster N TCR at 3,075 pounds.

Book It

Broadcaster, writer, driver, Motorsports Hall of Famer and Lime Rock legend Sam Posey has completed his latest book; “Sam’s Scrapbook” My Motorsports Memories by Sam Posey with John Posey.

Sam was the first driver to break the one-minute barrier at Lime Rock Park, where the front straightaway is named in his honor.

Tire Allocations

WeatherTech Championship
GTLM: 10 sets
GTD: 6 sets – S9M
Michelin Pilot Challenge
GS: 5 sets – S9M
TCR: 4 sets – S9M+

Lime Rock Park IMSA Records (all set in 2019)

Qualifying
GTLM/Laurens Vanthoor/49.133 seconds
GTD/Trent Hindman/51.456 seconds
GS/Owen Trinkler/53.963 seconds
TCR/Michael Lewis/54.034 seconds

Race
GTLM/Patrick Pilet/50.757 seconds
GTD/Matt Campbell/52.048 seconds
GS/Robin Liddell/54.446 seconds
TCR/Stephen Simpson/55.025 seconds