Keeping fuel in a NASCAR Winston Cup stock car seems fairly simple on the surface-the car starts the race on a full tank, then the pit crew adds fuel throughout the race. Behind all of that simplicity, though, is a lot of work.
The Winston Cup racing gasoline is 110 octane, and cars get anywhere from 2 to 5 mpg, depending on the track. Assuming that a car is getting 2.5 mpg, the total amount of fuel used per car during a 500-mile race would be about 200 gallons. At that rate, a full field of 43 cars would consume about 8,600 gallons of fuel if every car completed every lap. The retail cost per gallon is $4.25.
Every team begins the race with a topped-off tank in the car. Because every drop is important, the team shakes the rear end of the car to make sure there are no small air pockets when the 22-gallon tank is nearly full. The amount of fuel a team can use during the race is unlimited.
Each team can have three gas cans behind the pit wall. The crew can get 22 gallons of fuel in the car in less than 10 seconds. The fuel strategy throughout the race often becomes a follow-the-leader routine, unless they are exactly sure of fuel mileage. At this point, teams don't measure fuel in gallons; they measure it in pounds, and base fuel calculations on weight. This allows for more precise measurement and calculations. Every drop counts.
The process is simple, but the timing has to be right. First, the fuel cans are filled at the pump, then they are wheeled to the pit.
When the car comes in for fuel, the scene is something like a ballet. As one can is emptied, it's handed off to the behind-the-wall fuel-can man, and the second can is used to fill the tank.
The catch-can man signals when the tank is full by raising his hand. He knows the tank is full because fuel will come out of the overflow tube and is caught in the catch can.
With the car full of fuel, it's back to the track for more competition.