DRAFTING - Involves aerodynamics, a car moving at high speed creates drag—air resistance. When a trailing car positions closely behind a leading car, it enters a low-pressure zone or vacuum, reducing its own drag. This benefits both vehicles; the trailing car gains speed with less effort, and the lead car experiences smoother airflow, also reducing its drag.
RUNS - Together, cars in a draft can achieve higher speeds than individual cars. When a car is on the tail of another, the leading car experiences increased pressure on its rear (due to the trailing car filling the low-pressure wake) and reduced drag, making it effectively more efficient.
PACK - The larger the pack of cars in the draft, the more effective this aerodynamic synergy becomes, allowing the entire group to sustain even higher speeds. This pack creates runs where one lane will move past another. Drivers at the front will skillfully change lanes to keep the lead or get the lead.
RESTRICTOR PLATES - Effective 1988 Daytona and Talladega ran restrictor plates to limit engine airflow, reducing horsepower and top speeds. This measure effectively bunched the field, fostering the close-quarters, pack racing that became a hallmark of these events.
TAPERED SPACERS - Today, NASCAR Cup Series cars use tapered spacers. These devices replaced restrictor plates, performing the same function but allow more throttle response than restrictor plates. Atlanta Motor Speedway, having been reconfigured for the 2022 season, is now part of this superspeedway circuit that utilizes tapered spacers.
SIDE DRAFTING - is employed when a car briefly pulls alongside another to disrupt its airflow and increase its drag, creating a passing opportunity. Specifically, side drafting involves the front fender of the trailing car creating localized turbulent air that impacts the rear quarter panel and spoiler of the lead car. This disrupts the lead car's clean airflow, increasing its drag and momentarily reducing its downforce, effectively slowing it down and making it vulnerable to a pass.
FUEL MILEAGE - is significantly impacted by drafting. Cars running deeper in the draft benefit from reduced aerodynamic resistance, requiring less throttle input to maintain speed. This results in substantially better fuel economy for cars positioned within the pack and they need less fuel when they pit makeing the pit stop quicker. The lead car constantly punches the largest hole in the air and always has the worst fuel mileage. This can become a critical strategic factor during green-flag pit cycles, as cars that have saved fuel might require less time on pit road.
