Low Groove
The low groove is the racing line that runs closest to the inside edge or bottom of a racetrack, typically near the inner boundary where the track meets the infield area.
When race car drivers compete on a track, they don't just drive randomly around the circuit. Instead, they follow specific paths called racing lines or "grooves" that help them go as fast as possible. The low groove is one of these paths, and it hugs the inside part of the track. Think of it like choosing which lane to walk in at a mall—some people naturally walk closer to the storefronts while others walk near the center. In racing, this choice matters a lot for speed and strategy.
On oval tracks, which are circular or egg-shaped courses commonly used in NASCAR and IndyCar racing, the low groove runs near something called the apron. The apron is the flat, usually lighter-colored surface that separates the actual racing surface from the grassy infield in the middle. Drivers using the low groove stay just above this apron, taking the shortest possible distance around the track.
The low groove isn't always the fastest option, though. Track conditions change throughout a race day based on weather, temperature, and how much rubber from tires gets laid down on the racing surface. Sometimes the low groove offers the best grip and speed, while other times a higher line on the track works better. Smart drivers constantly test different grooves during practice and races to find which one gives them the quickest lap times.
One advantage of running the low groove is that it represents the shortest distance around the track. In geometry terms, the inside of any curve is always shorter than the outside. However, this doesn't automatically make it faster because the low groove might have less grip, more debris, or could force the driver to slow down more in corners.
The opposite of the low groove is called the high groove, which runs closer to the outside wall of the track. Some tracks develop multiple grooves at different heights, giving drivers several options for passing and racing. When a track has multiple competitive grooves, fans often see more exciting racing because drivers can choose different paths and make passes in various spots.
In road racing, which takes place on courses with both left and right turns (unlike ovals), racers typically use the term "racing line" instead of groove. However, the concept remains similar—the inside line through a corner corresponds to what oval track racers call the low groove.
Understanding the low groove helps explain why you'll see drivers diving to the inside of competitors during passing attempts. By claiming the low groove going into a turn, a driver can sometimes complete the pass because they're on the shorter, inside path. However, the defending driver might protect this line by positioning their car to block access to it, which is a fundamental racing strategy.