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Demo Derby Rules

$500 TO WIN     $250 FOR 2ND PLACE


Applications for all derbies will be taken on a first come basis. Entry fee is $40 for the Regular Derby and $40 for the Compact Derby.


Car Heats:

Four heats, not more than eight entries in each heat. The last two running vehicles in each of the four preliminary heats shall advance to the feature event.


A consolation heat will be held for all other vehicles still capable to running, with the winner also advancing to the feature event.



REMEMBER: If it doesn't say you CAN do it, DON'T!

1. All derby vehicles will be trailered to the inspection site of Hardin County Fairgrounds. Vehicles shall remain trailered until they pass inspection and are told where to unload. Driving or towing a demolition vehicle to Hardin County Fairgrounds is not acceptable. People in violation of state laws or local ordinances will be turned over to law enforcement and not be allowed to run in the derby - no refund will be made.


2. All drivers under 18 years of age MUST have notarized permission form filled out and signed by a parent or legal guardian and must possess a valid driver's license.


3. No passengers in derby vehicles anytime they are being operated.


4. Entries will be accepted up to two hours prior to start of the derby.


5. NO alcohol or drugs will be tolerated. Law Enforcement will be notified and violators will be removed from the fairgrounds.


6. Conduct of a driver, his crew members or friends, can disqualify the driver from the event.


7. Drivers are required to wear crash helmets and safety glasses/goggles or face shield. Drivers are also encouraged to wear fire retardant overalls. Driver must remain in their vehicle during the derby with their helmet on and chin strap fastened. A driver shall be disqualified for failing to do so. Seatbelts are required and are to be fastened at all times while operating a derby vehicle.


8. Only the driver will be allowed to speak to the officials regarding the derby.  Absolutely NO pit crew member or fan will be acknowledged.


9. A protest will cost $100 cash upfront. If the challenge stands, the money will be returned. If not, the money will be forfeited and turned over to the driver of the vehicle being challenged.


10. Derby officials may require a driver to remove or change any part or portion of a vehicle which they consider to be unsafe.


11. Absolutely NO hitting the driver's door of an opponent. Officials will determine weather it was accidental. First accidental hit will result in a warning. The driver will immediately be disqualified upon a second accidental hit or an intentional hit to the opponent's driver's door.


12. All drivers must attend a driver's meeting at the entrance to the derby arena one hour prior to the derby.


13. If necessary, officials will deal with any situation not covered in these rules. All decisions of the officials are final.


14. Remember - The Hardin County Fair is a family event. Please demonstrate good sportsmanship and have fun.


15. Drivers must hit an opponent at least once every minute. Sandbagging will NOT be tolerated. The derby will be stopped and the sandbagger's car will be marked with a double 00 to signify to other drivers who the sandbaggers are. If a driver is caught sandbagging after already being marked with a double 00, the driver will be disqualified.




Registration and Rules apply to the Full Size and Compact Derby also.


1. Passenger cars only. No trucks, pick-ups, Jeeps, hearses, or commercial vehicles. No imperials or imperial subframes.


2. All glass must be removed from the vehicle.


3. Radiator must remain in its original manufactured position. If it is removed, the block may be filled with water only - if radiator remains in stock position, overflow must point down at the ground.


4. Original gas tank must be removed. Metal marine gas tank shall be used. Tank must be secured to the floor by straps and bolts. Tank shall not hold more than 6 gallons of gas.


5. Bumper height shall not exceed 21" from the ground to the bottom of the bumper.  Bumpers must be stock automotive bumpers. No other re-enforcement. No trailer hitches, or bumper mounted trailer balls.


6. Hood and trunk will be chained or bolted. Exhaust is preferred to be upright out of the hood. There must be a hole in the hood surrounding the carburetor for fire extinguishing.


7. All doors must be chained - no welds, except driver's door. Welds must be approved by an official.


8. Driver's door is to be painted white.


9. No welding or additional re-enforcement will be allowed to any part of the car except the driver's door. One safety bar is allowed to run parallel along the dash and one behind the driver's seat. Bar shall not be any larger than 3" in diameter.


10. No solid tires, no filled tires including foam, water, cement, etc. No studs, chains, etc.



12. ONLY Full Size Class minimum wheelbase 110". 





1. All rules from the full-size derby apply to the compact with these additional rules.

            A. To be in the compact derby, the car must be a manufactured stock four or six-cylinder car. Front wheel drive only, with a maximum wheelbase of 110". Call or email with questions.

            B. Most four-cylinder cars have the fuel pump in the gas tank. If the tank is located in the front of the rear axel, the tank does not have to be removed. It also is not allowed to have more than six gallons of gas in it. If an electric fuel pump is used, the driver must have a shut off switch within reach. If the fuel pump is not located in the tank or it is located behind the rear axle, the tank must be removed. A metal marine tank shall then be used. Tank must be strapped and bolted to the floor and not hold more than 6 gallons of gas.


2. This is an economy class. NO welding, stock only cars. If it does not pass inspection, you can run with the big cars.


3. NO Changes. Example: stock size tires.

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