On Saturday, the North American sports car season will conclude with the Petit Le Mans, a 10-hour race to be held at Road Atlanta in Georgia. This year’s Petit Le Mans is also the latest race for a fan-favorite car class known as GTLM. The category included Le Mans-legal versions of two-door series cars, which over the years have been a playground for programs supported by manufacturers and some of the best racing drivers in the world.
On the one hand, the GTLM cut is a huge step for the US side of endurance racing, as it ends a direct link between the WeatherTech SportsCar Championship and the annual 24 Hours of Le Mans. But the move also makes the sport a little less complicated.
“Even some of the most avid motorists have a hard time understanding why the red BMW is so much faster than the yellow and blue one or [why] the red, white and blue Porsche is much faster than the # 9 or the # 16 or the # 88, “said John Doonan, president of the International Motor Sports Association (IMSA), the organizer of the sport.
Next year, IMSA will still have a seat for factory teams, but it is switching to cheaper and easier to drive cars with the introduction of a new class, called “GTD-Pro”. Let’s take a look at what’s going on.
The WeatherTech series has its roots in the first Petit Le Mans, which took place in 1998. That race adopted the same technical rules used by the Automobile Club de l’Ouest, the organization that manages the annual 24 Hours of Le Mans , France. Among these rules were the categories for modified racing versions of road cars. This is where things get complicated, so be patient.
Originally, there were two GT classes, called GT1 and GT2. GT1 cars were more highly modified, more powerfuland more expensive to run. They also generated greater aerodynamic downforce. Eventually, the category became too expensive and disappeared. GT2 got stuck and was renamed GTE in Le Mans and GTLM in IMSA competition (because having a GT2 class but no GT1 class made too little sense, even for an unnecessarily complicated sport like endurance racing).
In recent years, the same problem that killed GT1 has come for GTLM / GTE. Cars have become increasingly specialized; For instance, Porsche has taken the trouble to make a mid-engined 911 race car. And that has made vehicles more expensive to promote, particularly for the private teams that are the lifeblood of the sport.
Instead, those privateers have largely switched to a different category of production sports cars called the GT3. This category was created especially with amateurs in mind, even going so far as to impose driving aids such as anti-lock brakes. The performance differences between the various car brands have been adjusted to maintain a relatively fair playing field (known as “performance balance” or BoP), and the result has been a complete grid in racing around the world.