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Car preparation


The 24 Hours of Lemons gives everyone from novices to pros a chance to race on the cheap–and a chance to build a car like they’ve never built one before. Whether you’re an expert or newbie, it pays to read the rules closely and tackle this stuff step-by-step.

Lemons is all about racing crappy cars—you’re not a true gearhead if you don’t enjoy watching a rusted-out Volvo dice with a barn-find Corolla. But remember, a crappy car can bite you just as fast, if not faster, than an F1 ride. That’s why the bulk of your Lemons build is likely to center on mandatory safety improvements, and why safety stuff doesn’t count toward the $999 limit. It’s also the reason we make every car go through a full tech inspection before every race: If you cut a corner somewhere, our inspectors are just dying to catch you.

For rookies, the list of mandatory upgrades might seem intimidating, but remember that nobody expects you to do it all by yourself. Just take it a step at a time, ask questions about things that confuse you, and you’ll see that it’s not all that hard.

If you’re just starting out, set aside some time and money for high-quality, professional assistance on big stuff like the rollcage. (If you just rely on your old drinking buddy Jimmy to zap up a cage with his $200 home welder, there’s a pretty good chance that he’ll botch up the job or violate his parole before finishing it.) But remember, here, we said “high-quality” professional help. We’ve seen cages from “Joe’s House of Racin’ Stuff” with lousy welds and improper bends too.

There are several key areas Lemons’ tech inspectors will be focusing on:

  • Roll cage
  • Driver’s seat
  • Racing harness
  • Fire extinguisher
  • Fuel tank
  • Fuel system
  • Electrical cut-off switch
  • Race number

If whoever is doing the work is uncertain how to proceed don’t wait until tech inspection that you guessed wrong, Ask!!!

Keep reading to learn about these one by one. Just remember, this is car racing, not rocket science: A Lemons build isn’t that different from any other roadracing series’ requirements, and if those dorks can handle it, so can you. Best of all, once you’ve done it, you’ll either be able to re-use the same car again and again, or knock out another one in a quarter the time. We’ve seen some Lemons machines compete in eight or nine races without major updates. Apparently, some people just like the punishment.

Give yourself plenty of time, familiarize yourself with the rules, and enlist expert help where needed. Next thing you know, you’ll be on the grid—and probably wondering why you didn’t just take up gardening as a hobby.

Overwhelmed by all this tech stuff? drop a line to sean@24lemons.com.au


We suggest you purchase 2 radios (walky talkies) for driver communications with your team.


One of the most frequently asked questions about Lemons is “How do you count the laps?” After responding “C’mon, does it really matter?” we’ll tell you that we keep track of laps using electronic transponders mounted in each vehicle. The transponders work more or less like supermarket checkout scanners, except that they cost close to $999 each and we’ll have to charge you if you break one—more on that later.

If you already have an AMB transponder, you’re free to use it in the Lemons. Just input your transponder number on your team’s registration page before the race. If you don’t have one, you’ll have to rent one from us at a cost of $50 for the weekend.. You MUST return their transponder at the end of the race….or you get sent a bill for $300.00.

The transponder system scans the car from the bottom, with a signal traveling from the transponder in the car to a receiver loop embedded in the track surface. The transponders project their signal from the bottom of the unit while holding it vertically—the side opposite the flashing light. This transmitting side must be pointed toward the ground at a maximum distance of 30 inches from the track surface, with a clear visual path to the pavement. There should be no metal panels, brackets, suspension parts, or other components that could get in the way of the transponder signal. For the best possible results, the bottom of the transponder should protrude slightly beneath whatever it’s mounted to, and be insulated from any metal surface with a thin piece of plastic. The transponder can be mounted toward the front or the rear of the vehicle.

Your transponder should be located in a place where it won’t get damaged in an accident—don’t stick it on your bumper or anywhere else on the perimeter of the vehicle. The outer surface of the spare tire well is often a good spot, as is the rear passenger-compartment bulkhead–again, for best results, the transponder should protrude slightly from the bottom of whatever surface you’re mounting it to.

Some teams have gone to the trouble of cutting a hole in their floor and sinking the bottom part of the transponder through it. This method has extremely spotty results in our experience. Unlike the “outside-spare-tire-well mount,” which blocks the transponder signal from only the mounting side, the “hole” mount potentially surrounds the transponder with metal on ALL sides, greatly increasing the chance of scattering the signal. Also, if you do stick your transponder through a hole, it must protrude at least 2/3 of the way through–it can be tough to find the right balance between having enough clearance through the hole and putting the transponder too far into harms way. If you get black-flagged for a bad transponder signal, and you are using a hole mount, we will always tell you to use a different mount.

Regardless of where you mount it, it should be securely attached—usually, three or four sturdy zip-ties will do the trick.

Finally, remember that if your transponder comes back broken, we’ll charge you the full replacement cost, which might be more than your entire Lemons car is worth.


All Lemons cars must be fitted with a fire extinguisher, which should be positioned so that a fully harnessed driver can reach and remove it—practice this before the race.