Why NASCAR cars don't have gas gauges
The recent rash of gas shortages on the NASCAR circuit has brought to the forefront an often overlooked detail of the highly-complex NASCAR racecars. That is, they don't have one thing most of us a take for granted, a fuel gauge to indicate to the drivers how much gas they have left.
The simple explanation is that, like other information-gathering devices, they are not allowed in the car by NASCAR. In addition, a typical fuel gauge wouldn't work in a racecar because they are often driven at steep angles and bouncing all over the place -conditions that are not ideal for fuel measurement. So something else would need to be used.
But beyond that, they are simply not needed because the crew is able to accurately calculate how much fuel a car has left anyway. Joey Logano explained this in part on "The Dan Patrick Show."
"It's up to the engineers and the crew chief," Logano told Patrick. "They do such a great job on being able to calculate how much fuel we have in the car and how much we need to save. And we talk about it a lot. We don't really need a gas gauge. We're able to calculate it so well by the lap times we're running and we have strategies on how much I need to save as a driver and what I need to do."
In other words, the calculations are probably more accurate than any gauge would be.
Teams are so good at calculating fuel usage that with about 10-15 laps left at Watkins Glen most teams had a pretty good idea of exactly when their driver would run out of gas if they kept pushing their car. Matt Kenseth's crew knew their driver had 10 laps of fuel left with 11 laps to go.
Other drivers had even more precise measurements. Dale Earnhardt Jr.'s crew told him he would be 3.5 laps short.
The reason drivers at Watkins Glen ran out of gas wasn't that they didn't know how much fuel they had left. They ran out of gas because there were no caution flags for the last 30 laps despite 16 yellow flags in the first 60 laps and at least one caution in the final 20 laps of the previous seven races at this track. Caution flags allows cars to come into the pits for more gas without losing an entire lap to cars that don't need more fuel.
So, in the case of the Watkins Glen race, it was more about bad luck than bad knowledge.