Water Ballast in Tires

What happens here

To manipulate car weight for inspections, teams employed a tactic involving water-filled tires. The mechanic explains that they would secretly fill the inner liner of the right-front tire with water, adding approximately 200 pounds of weight. This ensured the car met the minimum weight requirements during pre-race technical inspections. After passing inspection, the team would intentionally puncture the inner liner on pit road, often with a nail, to simulate a legitimate flat tire. NASCAR rules at the time allowed one tire change without penalty in such circumstances. During this pit stop, the heavy, water-filled tire would be replaced with a standard, lighter tire. This effectively reduced the car's overall weight by 200 pounds for the race, significantly improving its handling and acceleration. The mechanic also briefly alludes to placing solid lead shot in the car (using a 'bombs away' signal) which could be dropped on track, although this isn't demonstrated.

Goal: Reduce car weight after inspection for improved race performance.