High Tech Auto Racing Fuel

NASCAR is using a 15 percent ethanol blend to fuel all its cars this season. In this interview, Sunoco vehicle test engineer Mark Borosky explains how the fueling process works once the cars get into the pit.

Pit crew members add the fuel from special cans that Borosky designed himself to recover all the vapors. Borosky says the fueling system needs to be closed, with no outside elements coming in, because the alcohol in the fuel can absorb water from the outside air. Having water in the fuel mix could cause the water and alcohol to separate from the rest of the fuel, and damage the engine.

The fuel needs to be dispensed from the special cans because not all the underground fuel tanks at the tracks are compatible with the new fuel blend. The older fiberglass in the tanks can degrade the fuel. Borosky says a newer version of the fiberglass tanks is needed. The compatibility is also a problem in making the fuel widely available commercially.

Borosky says the racing teams are adapting well to the new fueling procedure. He says it was used in the Truck Series last year, so the pit crews are used to using it. Borosky demonstrates how the fuel is dispensed using an airtight fitting. It's a coaxial fitting, with the fuel on the inside and the vapors on the outside, so the vapors are returned to the can. The fuel is put into the cans through a third valve, similar to a standard auto fuel tank fitting that allows the system to remain completely closed.