5 Things That Happen After a Bonneville Record Run

The starter points you off. The bump of the push truck on the rear of the car gives you a little reminder that it’s time to go real fast. You hold the throttle down through the timed miles, throw the parachute, and begin your slowdown, coasting into the chase road on the left. Your crew and push truck arrive with a big burst of energy after the radio calls “that’s a record! Congratulations, take that car to impound for certification.” Think the hard part is over? Not so fast.

Bonneville Speed Week has a lot of unique intricacies in how it runs relative to other motorsports events. The goal for any racer out on the salt is to set a record by going as fast as they can over the five-mile straight-line track. It sounds too simple, and to a point it is, but like so many other forms of racing, the going fast is the easy part compared to the rest. While out at Speed Week 2024, we took a look at the process that follows a record setting run. Here are the highlights, just so you’ll be ready.

The clock starts

In the flurry of excitement and adrenaline that floods the brain after a speed run, it might be temping to forget about the clock for awhile and revel in the moment. That would be a mistake. The challenge is not over yet.

You have one hour to get to the designated impound area where your car will be held and inspected to confirm the record. This means squeezing out of the car, collecting your parachute, getting the car connected to your tow rig and turned around, and respecting the 45mph chase road speed limit for a few miles until you can turn into impound, where the kind volunteers of the Southern California Timing Association will start the confirmation process.

Pick up your timing slip

On your way to impound, be sure to stop at the trailer that prints off the timing slips showing your average speed for each section of the course. The inspectors at impound will need to see that slip, and you’re going to want to frame it for your office.

If this run was your record qualifying run, your car will go into impound where you will only be able to perform basic maintenance and prepare for your back-up run. All work can be monitored while in impound to prevent any funny business. For 2024, the SCTA added a small window in the afternoon that allowed those in impound to run their back-up run the same day at 4pm if they so chose. Otherwise your car will be camped in impound overnight before you go out and repeat your record run where you will start at step one again and proceed past this point where…

Your engine displacement will get confirmed

Many of the classes and records on the salt are determined by engine displacement. This means that in order to confirm a record, technical inspectors need to confirm your engine is indeed the displacement you say it is. Occasionally this is easier said than done. Luckily there are two relatively painless options:

The first is to “pump” the engine. This involves removing the spark plug of the inspector’s choice and assisting in connecting a hose and chamber that are similar to a compression tester, but rather than checking how effectively the piston and cylinder compress the air and fuel, it tells the volume of air pushed from the cylinder during the compression stroke. That measurement, multiplied by the number of cylinders in the engine, gives the total displacement.

The second option involves a little more math and a lot more precision. A spark plug is removed and through the plug hole a rod is inserted while that piston is at bottom dead center. From there the engine is turned until the piston is at top dead center and the rod is used to measure the stroke. Then a very small set of telescoping gauges is used to measure the bore. From there it’s stroke x 3.14 x (0.5 x bore)² x number of cylinders = total displacement.

Your seals will get inspected

Just like the engine displacement, what fuel that engine runs on will also determine the car’s class. Racers have essentially two options: Gasoline or “fuel.” Any fuel used that is not one of the nine approved options—which also have to be pre-ordered and delivered direct to Speed Week for pickup—immediately puts your car into the “fuel” class. To keep things on the level, anyone running in the gas classes must fill their fuel tank under supervision of an SCTA official who subsequently puts a seal over any fill ports to ensure the fuel used during a run is what the team says it is. These seals must still be intact upon inspection in impound to qualify for a record.

You’ve gotta sign some paperwork

The final step is to put a few names on the dotted lines inside your logbook and on a few official forms that document all the details you and the tech inspector just confirmed. Only after all the paperwork is signed and submitted do you have your record. Shake hands with your inspector and get your car back to your pit. Now you are left with the option: Celebrate or start preparing to beat your own record.