Grassroots Motorsports $2017 Challenge Rules


Read all the rules and still have questions? Check out our Rules FAQ at the bottom of the page.

The Basics:

This event is meant to be a fun editorial exercise so Grassroots Motorsports can show its readers what creative people can do with a car, their hands and a little cash. Cars found in violation of the spirit of the event may run for exhibition.

Competition Venue:

The competition will cover three different arenas: autocross, drag racing and concours judging. 

The autocross will follow standard autocross rules. Each cone knocked over adds a 2-second penalty to the run time. An entry’s fastest single run (regardless of driver) will be used for scoring. Entries will be guaranteed a minimum number of runs TBD prior to the event start time based on entry numbers.

We will again offer pro drivers for those who are not Mario Andretti. Entries will be guaranteed a minimum number of pro driver runs; this number is TBD based on final entry tally and will be announced prior to the event start time.

Pro drivers, and entries that have made fewer than their guaranteed minimum number of runs will be given priority access in staging lanes.

The drag racing will follow standard drag racing practices. Competitors will be given ample time for drag race runs, with their quickest elapsed time counting.

Red light runs will not be counted. Runs that are completed in violation of NHRA rules will be not be counted. (See “Safety” section of the rules for more information.)

Since the drag racing will again take place after dark, all entrants must have at least one operational headlight and at least one operational taillight. 

The third venue will be concours judging. Cars will be parked in a centralized location, with hoods, trunks and doors opened for the judges and competitors to view. Entrants will have 3 minutes maximum to present their cars and share their story with the judges. If we like you and/or your story, some bonus time may be awarded. Cars will be judged on innovation, execution and presentation, and scoring will be as such:

Innovation: 0-10 points

Execution: 0-10 points

Presentation: 0-5 points

“Innovation” covers things like design, engineering, creativity and modifications.

“Execution” covers things like cleanliness, workmanship and attention to detail.

“Presentation” covers things like originality, theme, showmanship, team spirit, moxie, chutzpah, backstory and anything else that falls under the heading of “je ne sais quoi.”

Any entrant that does not want to go through the concours judging process may decline to be judged by writing "Don't Judge Me" on a piece of tape placed on the upper driver-side corner of the windshield of their car. Cars properly displaying this message that are parked in the centralized concours judging location for the duration of judging will be awarded 12 concours points. 



Entry fee will be $175 for the entrant and vehicle and 1 banquet ticket. Each additional teammate/driver/banquet ticket costs $65. Thirty days prior to the event, the entry fee shall go up to $225. Cancellations will be credited to the next year’s entry.

All drivers shall have a valid state-issued driver’s license and be at least 16 years of age. All passengers shall be at least 16 years of age.

Eligible Vehicles:

Any four-wheeled, production-based vehicle that was originally sold as a passenger vehicle is allowed. (You know what this means, but generally speaking we’re going to want to see production frame rails or equivalent unibody structures.) Vehicles that don’t fit this category or exceed budget may be run for exhibition only at the event chairman’s discretion.)

We do not intend to exclude any past Challenge cars with these new rules. If you believe that your past Challenge car meets the spirit of the rules but not the exact letter of the new law, contact us to discuss grandfathering in your entry.


Net cost of the Challenge car and its preparation for presentation at the event must be equal to or less than a dollar amount equaling the year of the competition. Your purchase price of the Challenge car cannot top that year’s budget cap. 

Up to half the total annual budget may be recouped by selling parts originally included with or attached to the Challenge car, related parts car(s), or related parts packages at the time of purchase. You may not factor gains or losses made from buying, selling or trading unrelated parts into your budget. 

You may never recoup more than a part or car’s purchase price or fair market value (whichever value you listed on your budget sheet.) You may not list fair market value instead of purchase price on your budget unless you do not have a receipt from the purchase, or depreciation/appreciation has drastically affected the car or part’s value.  Free parts must be known to and available to the public (eg. sitting in a ditch on the side of the road). “Free” parts given to you by a friend must be added to the budget at fair market value.

In English, what does this mean?

For 2017, the budget cap is $2017.

For 2017, the most you can recoup through parts sales is $1008.50.

For 2017, the max you can initially pay for a Challenge car is $2017.

If you buy a part for $40, decide it won’t work, then resell that part for $50, you may not recoup $10. Leave this unrelated transaction out of your budget sheet entirely.

If you buy an engine for $100, use the heads on your Challenge car, then resell the rest of the engine for $80, you may recoup $80, assuming your build has not already hit the recoup limit.

If you buy an engine for $100, use the heads on your Challenge car, then resell the rest of the engine for $300, you may recoup $100, assuming your build has not already hit the year’s recoup limit.

If you bought an engine last week for $800, but the fair market value is actually $200, you must still add it to your budget at $800. 

If, 30 years ago, you bought an engine for $800, you may add it to your budget at today’s fair market value if you desire to.

Fluids (including gasoline, oil and brake fluid) are not required to be included in the budget. Nitrous oxide refills do not count toward the budget (however, the cost of the equipment that comes along with a nitrous setup does need to be added to the budget). Nominal amounts of grease (such as what’s required to pack bearings) do not need to be included in the budget. 

Costs to pick up your hooptie from the seller are exempt.

Title fees and so on, in case you bothered, are exempt.

Shipping counts toward parts prices. Sales tax does not.

These safety items are budget-exempt: seat belt or harness; fire extinguisher; roll bar padding; wheel lugs, studs and bolts, and four tires. Brake friction materials, lines, calipers, master cylinders, rotors and drums may be replaced with fresh ones that are functional duplicates. The purpose of this rule is to allow for fresh brake components, not to allow for budget shenanigans. For example, original brake parts cannot be sold and then re-bought to take advantage of this allowance.

The Reese Rule: SFI-approved harmonic balancers, SFI-approved flywheels and SFI-approved flex plates are budget-neutral. These parts are dangerous rotating assemblies that should be treated with respect. Any intact harmonic balancer, flywheel, or flex plate listed on the budget may be exchanged for a duplicate SFI-approved part without increasing or decreasing the budget. “Duplicate” is defined as having the same listed application as the standard part in a major parts catalog. In situations where a standard part is not present to exchange, fair market value of the standard part may be used.

SFI-approved transmission shields, SFI-approved flex plate shields, and SFI-approved bell housings are not rotating parts, and are not budget exempt. You may still be required to use one or all, depending on your car’s construction and E.T. in the drags.

Any inside deals—parts, whole cars, trades, donations, stolen parts, etc.—must be added to the budget at fair market value. If you can’t figure out the value of a part, ask on the message board at

Labor you perform yourself does not count. Any labor you pay for counts. If you run a shop and your paid employees work on the car, then it counts.

The Stampie Rule: We’re sorry that your car is having an issue at the event, but we can no longer turn a blind eye so you can get back in the game. Parts borrowed at the event must be added to the budget at purchase price or fair market value. If two builds elect to share parts at the challenge, such as a set of wheels and tires, then the parts must be included in both builds’ budgets at the full purchase price or fair market value.

Crapcan Clause:

24 Hours of Lemons race cars are automagically legal, provided they meet the spirit and intent of our rules.


If a competitor or competitors feels that another competitor has skirted the safety or budget rules, a protest should be lodged. Protests should be lodged in a timely fashion, with none being accepted later than two hours before the start of the awards banquet.

Step 1: Notify the event chairperson that you intend to lodge a protest.

Step 2: Deposit $50 cash with the event chairperson.

Step 3: Clearly and concisely describe the competitor you’re protesting and the part or practice you feel is in violation of the rules.

After fulfilling these steps, the GRM staff will assess the vehicle in question. If the protest is valid, the car in question is penalized at GRM’s sole discretion and the protestor(s) deposit is returned. If the protest is not valid, the protestor(s) forfeit their deposit.


Cars should have a finished appearance. Use good sense and taste when you modify your car, as missing grilles, headlights, fenders, hoods and the like are generally unattractive. Cars that are ugly will be less likely to be featured in the magazine and other media. Please remove your front license plate and plate holder, as those things are ugly, too.

GRM will provide required number panels to all entrants. If you have a theme that doesn’t work with these panels, then concessions can be made. Please discuss with the GRM staff prior to the event.

Sponsors make this event possible, so GRM reserves the right to require a windshield banner, as well as the right to require that competing companies’ decals be removed or covered during the event.


All entrants shall provide a three-ring binder (referred to as the “build book”) to GRM at registration. Each build book must contain, in this order:

A single, large photo of the car (the more recent, the better).
Your completed vehicle information form.
On one page, a list of the first and last name of every team member, along with their role on the team (eg. Rick Goolsby: Welder).
The story of your build. Use as much text and as many photos as it takes to explain how and why you built the car you built.
Complete build budget on GRM-provided spreadsheet template. Minimum font size is 12pt typed. Handwritten budgets will not be accepted. 
Every receipt referenced in the budget. Photocopies are acceptable. 
Supporting documentation for every fair market value calculation used in the budget.

Number panels will be issued once your completed build book is received. Build books will be available for public viewing throughout the weekend at the GRM booth. During the concours, build books will be handed out for display with each car. Each team must return their build book at the conclusion of the concours.

Click here to download the GRM budget spreadsheet template, which includes an example budget on sheets three and four to show how the template should be filled out. When printing your budget for your build book, please print only sheets one and two, not the example sheets. Please do your best to print your budget in a readable form–ex. not spread across 15 pages, and not including 100 unused rows. If you do not have Microsoft Excel, free alternatives are available that can open this spreadsheet. We suggest Google Sheets or Apache OpenOffice. Budget documentation questions can be answered via email:


The following will be required: all lug nuts present; two functioning throttle return springs; positive battery tie-down; properly operating brakes; wheel bearings free of excessive play; properly secured seat; and tires free of any exposed cords or other defects. Additionally, all loose items shall be removed from the interior, and open cars running non-DOT race slicks must have approved rollover protection and arm restraints. Cars that do not meet the SCCA’s Static Stability Factor will not be allowed to run. 

Drivers must wear a helmet at all times. NHRA rules require drivers wear a SFI 3.2A/1 Jacket or better in vehicles equipped with non-OEM nitrous oxide, turbochargers or superchargers that run a 13.99 or faster E.T.

We want to see safe cars. We don’t want to send anyone home without getting to compete. Building something radical and not personally familiar with the NHRA standards? Tech inspection at the track isn’t the place to learn.

Please discuss your build with GRM staff ahead of time so you arrive with something that is safe and meets the NHRA regulations. Does it have a suitable firewall? Did the welding properly penetrate the metal? Is the harness properly attached? Is the roll bar suitable? Is a legal windshield present? Is your new layout safe and sound?

We recommend you have the car inspected locally and ahead of time by a qualified SCCA or NHRA inspector so no surprises crop up at the event. Failed cars will be reinspected after fixes are made. Entries that fail onsite tech inspection will not be allowed to run.

Cars must meet the safety requirements of the SCCA Solo program while running the autocross, and the NHRA when running the drag strip. Your safety prep level will limit your drag race times. To discourage bonsai runs, cars that run quicker than their safety prep level allows will not be given a time for that pass, and may be barred from future drag passes. Five-point roll bars meeting item 4:10 of the NHRA's general safety regulations are mandatory in all open-top cars running a 13.49 E.T. or faster. For a summary of NHRA’s safety rules, click here.

From the NHRA rulebook: If no specific Protective Clothing requirements are stated for a particular class, then the minimum requirements are as follows: full-length pants; short- or long-sleeved shirt; closed shoes; and socks. No shorts. No bare legs. No bare torsos. No tank tops. No open-toe or open-heel shoes or sandals. Synthetic clothing not recommended.

Those in the drag strip’s staging area shall follow the above clothing requirements. 

Autocross safety regulations will follow the SCCA Solo rulebook. Access it by clicking here. 

Teams that lose a wheel or send any other large or heavy item flying from their car will be disqualified from the event.


The dynamic score from the challenge will be calculated by adding the competitor’s fastest drag time and fastest autocross time together. This will give their “dynamic time.”

The lowest dynamic time is worth 100 points. Points for second and subsequent places are determined by dividing the winning time by each other time, then multiplying by 100.

For example, if the winning combined dynamic time is 74.2 seconds and second place is 75.0 seconds, the 74.2-second driver receives 100 points, while second place gets 98.9 points (74.2/75.0 = .989 x 100 = 98.9).

The maximum concours score is 25 points. The maximum possible total score is 125.

Highest score wins the overall trophy. The team that takes the overall win will receive free Challenge entry for the following year.

Rain-Outs and Other Excuses:

Your first run will be first come, first served. If you were unable to compete in any portion of the event because of mechanical failure, bad sleep habits, ennui or any other reason, you will be given an arbitrary score of 99.99 for timed events, or 0 for the concours.

If any part of the event is rained out, struck by a meteor, invaded by a flashmob of Michael Jackson impersonators, or otherwise seriously disrupted so that more than half the entrants don’t get a chance to compete, GRM staff may choose to discard that portion of the event from the final scoring. 


GRM reserves the right to issue competition bulletins at a later date.

One Final Word:

Remember, this event is all about having fun and being creative, and these rules supersede the ones from past Challenges. Have a question about the event? Just ask.

Rules FAQ


Q: What if I got four autocross tires for free, and bought 4 drag tires for $200? Can I claim my drag tires as my “free” set.

A: In this case, you may technically be able to claim all eight tires as free. However, remember that free parts must be known to and available to the public (eg. sitting in a ditch on the side of the road). A second set of tires that was given to you by a friend or acquired via any other non publicly-available transaction must be budgeted at fair market value.


Q: I want to put a T56 transmission into my Honda Civic, and I know that I need a stock flywheel from a Camaro. Because SFI-approved OEM-replacement flywheels are budget exempt, I can buy a new SFI-approved Camaro flywheel and value it at $0 on my budget, right?

A: No, that is not correct. In this scenario, you may exchange the Camaro flywheel for an SFI part. Bought an OEM Camaro flywheel for $20? Include that receipt in your budget, then you may use an SFI-approved Camaro flywheel without any additional budget impact. If you don’t currently own an OEM Camaro flywheel, you may list its SFI-approved replacement at the standard part’s fair market value on your budget.


Q: Can I run an over-budget car just for fun?

A: If your Challenge car fails to make the event due to technical, logistical or metaphysical issues, we may allow teams to run an alternate vehicle for exhibition. Please do not register a rental car or other extremely over-budget car for exhibition if you never intend to build a Challenge car.


Q: Can I field a car by myself?

A: Yes, one-person teams are welcome.


Q: Can I camp at the track?

A: Sorry, no camping allowed at the track. 


Q: Is there fuel available at the track?

A: Yes, the track sells race fuel. Hours are limited, so plan ahead.


Q: Are media passes available?

A: They certainly are. Contact Rick Goolsby for details. 


Q: May I drink alcohol at the track?

A: No alcohol may be consumed at the track. This goes for drivers, crew and spectators.


Q: Is there power available at the track?

A: There is very, very limited available power, so plan ahead.


Q: Is there compressed air available at the track?

A: Yes, there is. 


Q: May I grill at the track?

A: Yes. And remember that the staff is often hungry. 


Q: It seems like a few of the NHRA rules will make my fairly average car illegal. What gives?

A: We realize that the rulebook has a few issues when it comes to this event. The following rules may be ignored if your car runs slower than 11.49 E.T.:

  • Windows must be rolled up during drag runs (if you don't have windows, you'll be required to wear a full-face helmet).

  • Welded differentials prohibited.

  • Mandatory C-clip eliminators. 

  • Partially excepted: Battery shutoff switches. Alternative construction and placement acceptable. Must remain within driver's and first responder's reach and be clearly labeled on the exterior of the vehicle.

Still have questions? Ask them here.