Hot Rodding Fuel Rigs

CAT 22:08:2024

Some races the fuel delivery can be covered by a stop for four tires. Other stops are a race to get the mandated minimum fuel drop into the car before release into the fast lane. It is most probably one of if not the most dangerous part of pit lane operations. The fuel rigs have been developed over the years to deliver race fuels fast and as safely as possible. To ensure teams are playing fair and not gaining an advantage by modifying their rigs or compromising safety, many fuel rigs use control parts to manage the rate fuel can flow through the system and into the car. Typically a fuel rig will have a set size and height for the fuel hopper. Fuel hoses will be a set diameter and the fuel coupling will also be a control part. Supercars use a control part in the fuel line to restrict the fuel rate. Gen 3 Supercars have a number of changes compared to Gen 2. Most noticeable is the fuel coupling being a single large attachment that clamps on when the refueling team member pushes it onto the car. When correctly clamped on fuel flows from the rig into the car, displacing the air in the tank that vents back into the rig. There are gains to be made in a race if a team can get their car out in front of a competitor, gaining track position or holding an existing position advantage. In races where on track passing is low the race into and out of pits becomes even more important. So far in Gen 3 races we have seen early problems with fuel flow rate for some teams. Some due to getting used to the new system for coupling up the fuel nozzle and some due to the setup of the fuel system itself in the car. Now the Gen 3 Supercars are in their second season all teams have had ample practice with their fuel rigs and mistakes with coupling the fuel nozzle to the car are more rare. So what else affects the fuel flow into the car? Position and height of the fuel rig. The height of the rig from the ground is controlled as per the specs on refueling from Motorsport Australia. All rigs should be at the set height. Temperature of the fuel will effect the amount as colder fuel takes up less space. Fuel coolers are not allowed to be used to chill the fuel towers or the hoses. The temperature of the fuel is effected naturally by the weather. Wrapping the fuel hoses with insulation is something we see in Supercars. The length and bore size of the hoses themselves is controlled. A minimum fuel drop is measured using a sight gage in Supercars. The ambient temperature of the day will have an effect on fuel volume. Very simply on a colder day 80 liters of fuel on the sight gage of a cold fuel tower will go into the car. The car fuel tank being hotter will allow the fuel to expand slightly and let you push a little harder on track than a team with a warmer fuel rig. The difference may be very small but races are often won or lost on fuel strategy. If the teams all practice well and the driver hits the mark allowing the refueller to couple up and let fuel flow, we should get a fairly even delivery across all teams. So the technique of the refueller is very important. Some teams we see the fuel hose over the shoulder of the refueller so less of the fuel hose hang down low. Some let the whole hose hang down low. It would be interesting to see some info on any gain with these two techniques if there is any. So what about hot rodding rigs to gain an advantage. Some elements like the weather are just natural and out of the teams control of course. Maybe chilling the garage area at the hotter events with a large air-con, that just happens to let a nice cold breeze flow towards the fuel rig. Maybe one end of pit-lane is slightly higher than the other and would give a very slight natural advantage. Preparation of the fuel rig itself would be very important with all inside parts polished and a perfect fit for all connections. What gray areas are there in the rules and specs for the fuel towers themselves? Expect all teams to have studied the rules and if there is any sort of advantage to be gained they would take it. In 1969 Penske built the most noticeable alteration to a fuel filling rig for its trans am running Camaro. It was called the Big Rig. It was simple in design using 20 foot scaffold lengths to raise a second fuel tank into the air above a smaller tank down low, set to the regulation height above ground. The tanks were double walled with 15 gallon drum inner tanks sitting inside 30 gallon drum outer tanks. The space between the inner and outer walls was filled with ice and acetone for maximum chilling effect on the fuel. After the first day the Big Rig was set up at the track, the rules were changed so it could not be used. What ever gains are to be found in the hot rodding of fuel rigs in current competition, they would not be ones we can easily see. If any one has any ideas to share on possible gains to make the fuel filling faster or ways to modify a fuel rig in the gray areas, please make contact. Respect to all the refuellers.