Michelin IMSA Insider: What CTMP’s Track Repave Means

What’s New?

IMSA’s return to the Canadian Tire Motorsport Park for the first time in three years will help reconnect manufacturers, teams, drivers, and fans old and new to the track.

The track diagram indicates that CTMP is the same 10-turn, 2.459-mile circuit as when IMSA last raced there in 2019.

Hans Emmel, the Michelin IMSA WeatherTech Championship series manager, does not think that is completely the case.

The iconic 50-year-old Canadian circuit was repaved early during the pandemic.

“The dimensions and layout of the circuit haven’t changed, but the track surface has and since the tires are the only part of the car touching that surface, the interaction is what we want to fully analyze,” said Emmel.

With border restrictions in place until very recently, IMSA teams and Michelin have not tested on the new CTMP surface.

What It Means

“When older, worn track surfaces are repaved, the new surface presents three factors for us to consider.

“The first is the grip level. New top surfaces generally yield a micro level of abrasive materials that can result in lots of small edges for tires to bite.  That generally translates into higher grip and quicker lap times,” said Emmel.

Times, Temps, Trims

The second factor is track temperature. A newly paved or resurfaced track is darker and absorbs direct sunlight more than an older surface that has faded over the years. On a sunny day, track temperatures can be much higher than previous measures of the old surface.

The third factor develops if the new track surface does have more grip, and teams may trim out a bit of downforce to take advantage of increased mechanical grip.

The combination of quicker lap times, higher track temperatures, and friction from a more micro abrasive surface can combine to increase tread wear.

Since the actual repaving was done two years ago, it has had time to cure and weather to age the surface. It is not yet clear if some bumps or surface transitions may have gone away, or new bumps appeared.

But, if conditions are favorable, the track record book may be in for a rewrite.

More to Come

CTMP is not the only circuit that is committed to a fresh surface. WeatherTech Raceway Laguna Seca and Road America have both announced plans to repave their circuits later this year. The 2023 Detroit Grand Prix will move from Belle Isle to a downtown street circuit.

“It is great to see promoters investing in their track surfaces. Drivers like to go fast and break records, and Michelin and the teams are really looking forward to CTMP,” said Emmel.