Diesel Cannonball

Diesel vehicles offer a strategic advantage for cross-country record attempts. Modern turbodiesels combine high torque for sustained high-speed cruising with exceptional fuel economy. A diesel can often travel 700+ miles on a tank, reducing fuel stops and time lost. The trade-off is slightly lower peak power compared to gasoline performance cars.

The stock BMW 535d carries 15.8 gallons in its factory tank, which at Stowell's observed 23 mpg cruise average would provide approximately 360 miles of range before the fuel light appeared. Stowell's build added an aftermarket trunk-mounted fuel cell — likely a 29-gallon rated cell yielding ~24 gallons usable after foam displacement — that brought total usable capacity to roughly 40 gallons, extending theoretical range to over 900 miles per fill. The auxiliary cell uses reticulated polyurethane foam to control fuel slosh under hard braking and acceleration, a standard motorsport practice borrowed from endurance racing. The foam prevents fuel from sloshing away from the pickup under g-loads that would otherwise cause fuel starvation in a half-empty tank.

At 23 mpg average, 40 gallons yields 800-920 mile segments depending on driving intensity, which translates to three fuel stops across 2,803 miles. A comparable petrol performance car burning 13-15 mpg would require four to five stops on the same tank volume — the Toman/Tabbutt petrol car that set 25:39 carried 67 gallons of petrol in auxiliary tanks. Stowell's Garmin data shows 32:49 total stopped time across the country, of which 15 minutes were a police traffic stop in Oklahoma that had nothing to do with fuel strategy. Actual fuel stop time totaled 17:49 for the entire run, or roughly 5.9 minutes per stop.