What’s with the clamp on the wing? Why do racing fuel hoses have two lines? Why am I asking you all these things when the answers are in this video? FCP Euro highlighted a pit stop by one of the Marc Cars V8-powered Mazda3s at the California 8 Hours at Laguna Seca which explains it all.

Different series have different pit stop requirements. Some prevent you from doing anything but fueling when the fuel hose is in out of extreme caution. Others allow different numbers of crew members over the wall to work on a car at once, for example. As far as endurance racing pit stops go, though, this one hits all the high points.

The California 8 Hours at Laguna Seca was part of the. The team cleverly makes use of a ground wire to take static off the car and prevent fuel from sparking in the pits. Only four people are allowed over the wall at a time, and they can take care of the driver change while the fuel hose is in but nothing else.

The fuel lines are particularly interesting. One line of the two that stick into the car is a vent, which allows air out of the system in order to allow them to fuel the tank faster. Anyone who’s ever fumbled around with a gas jug should be familiar with the principle: if air doesn’t have an easy place to vent out of the fuel system as you’re adding more fuel in the tank, you’re going to be standing there fueling. Air that’s being replaced with gas in the tank is forced to bubble through the gas to get to the top of the bottle. The two lines prevent these irritating bubbles by giving air out of the tank somewhere to escape.

Something else you might not know: fuel has to be kept cool, as it’s denser at cool temperatures and more of it can go into a car’s fuel tank then. This is why fueling rigs tend to be insulated.

The car comes up on its air jacks next. These jacks pop out of the bottom of the car when they’re pressurized with air, lifting the car super-fast and letting the tire changers get to work.

The Intercontinental GT Challenge also has a minimum time for pit stops, necessitating 50 seconds per stop so no one rushes through anything too much and misses anything vital. As soon as one pit stop is done, they’re already preparing for the next one.

Also, we’ve mentioned it before and we’ll mention it forever and ever: stuffing a big V8 into a Mazda3 is one of our . That sound is wonderful.