RULES
ATV/UTV Classes
ATV/UTV Youth -
Need to be able to safely operate and control unit.
No paddle tires
850 cc engine maximum
Drivers feet must firmly reach footpegs
Pants and closed-toed shoes required
DOT approved helmet and eye protection
Chest Protector Required
Max age of participant is 13 yrs old
ATV/UTV Adult -
DOT approved helmet and eye protection
Chest protector required (Limited supply available if you forget to bring yours)
Pants and closed-toed shoes required
No engine CC limit
Paddle tires allowed
Any model/style machine allowed
Minimum age of participant is 14 years old
Subject to Safety and Tech Discretion
Street Class
Truck must be licensed, insured, and street legal per DOT regulations
All lights must work - includes headlights, turn signals and taillights
No BOGGERS or Bogger knockoffs!
NO aftermarket LOCKERS, SPOOLS, OR WELDED DIFFERENTIALS
FACTORY LIMITED SLIPS ALLOWED
No race fuel
E85 Allowed
No blowers, alcohol, or nitrous
No trans brakes
All other general safety rules must be applied
Must have closed toe shoes and pants (no shorts, spandex, crocs)
No ATV/UTV's
496 CI (8.1L) maximum motor size
Sportsman
TIRES
33" max DOT tire (sized by physical measurement)
Must be a mud tire (no straight tread tires)
No cutting or grooving
No paddle tires
ENGINE
Factory V-8 equipped trucks only
Roller rockers and roller camshafts allowed
Gasoline only, no strokers
No blowers, alcohol, or nitrous
Specialty race fuels allowed
Must be factory spec rotating assemblies including rods/cranks
Maximum engine size is 368 CI
No fuel injection (OEM or Aftermarket)
Any aluminum dual or single plane Intake manifold allowed ....NO sheet metal, tunnel rams or fabricated intakes allowed!
Carb swaps allowed - vacuum secondary, single pump only
Open header allowed - bottom exit only
Must run a steady 17 inches of engine manifold vacuum at 1000 rpm's for 30 seconds.
No vacuum pumps or equipment that will produce vacuum
Must have a fan shroud
Must have a vacuum line routed to front or side of engine compartment for easy access by tech personnel.
Aftermarket ignition is allowed.
Any Factory produced/released cast iron head allowed - No Aluminum Heads
Porting and polishing is allowed.
Approved transmission blanket or shield required on all auto transmissions, must have a flex plate shield to contain ring gear and converter if there is an issue.
Stall converters are allowed
No trans brakes
BODY
Complete body required, corp. matching make and model
Rear seats and tailgate may be removed
Must have 2 operating doors
Body and interior must be completely intact
Hood scoops allowed, must be rear facing, no isolation trays or plumbing allowed which isolate intake from engine compartment or to the bottom of the hood
Must have factory front bumper, tube bumper allowed in rear
Tilt front hood allowed, no gutting of hood
FRAME & SUSPENSION
Total body and suspension lift not to exceed 4 inches
Must be factory suspension, axle swaps allowed
Must have factory OEM unmodified frame
Must be factory transmission for that year, make, model
Aftermarket Transfer Cases Allowed
Driver must sit in stock location
Tow hooks required, front and rear
Fuel cells allowed, factory tank may be removed.
If fuel tank is mounted in the cab it must be removed.
Minimum 3 full length leaf springs required in rear.
DRIVELINES NEED TO BE PAINTED IN BRIGHT COLORS to be able to be located if dropped from vehicle
SAFETY
Must meet all safety requirements; Fire extinguisher, Helmet
5pt Harness Required
Single Layer Fire Suit Required
Driveline brake shielding highly recommended!
Minimum 3 working brakes required.
Super Stock
TIRES
38.5" max DOT tire (sized by physical measurement)
No cutting or grooving
No paddle tires
ENGINE
No aftermarket blocks allowed
Gasoline only, no nitrous, alcohol, or forced induction
Roller rockers and roller cams allowed
No aftermarket fuel injection
Big blocks allowed, must be in stock location
468 cu inch maximum, carb swaps allowed
No trans brakes/dump valves allowed under any circumstances!
Open headers allowed if exiting up or down, not out the side
Must run a steady 15 inches of engine manifold vacuum at 1000 rpm’s for 30 seconds for big block. Small blocks must pull 14" @ 1000 rpm
No vacuum pumps or equipment that will produce vacuum
Front or rear mount radiators allowed but must have shielding to protect driver in event of a leak
Approved transmission blanket or shield required on all auto transmissions, must have a flex plate shield to contain ring gear and converter if there is an issue.
Aluminum heads are allowed. The aluminum heads allowed will be limited to those cylinder heads with port architecture that will accept a factory cast iron intake and a factory exhaust manifold and will be functional with those manifolds.
BODY
Complete body required, corp. matching, make and model
Rear seat and tailgate may be removed
Must have 2 working doors unless open bodied
Body must be completely intact
Minimal fender well trimming to accommodate larger tires
Dash components may be removed (components only)
OEM bench seats allowed, racing seats strongly recommended
No fuel tanks inside driver’s compartment, this includes factory tanks mounted in the cab
FRAME & SUSPENSION
Total body & suspension lift not to exceed 6 inches
Axle swaps allowed
Must have factory OEM unmodified frame
Aftermarket Transfer Cases Allowed
Driver must sit in stock location
Engine, tranny, and chassis must be corporate matching
Tow hooks required, front and rear
Traction Bars Allowed
Factory OEM Style Suspension
Coilovers allowed in factory location; Subject to board approval
Minimum 3 full length leaf springs in rear
Must have drive shaft loops and u-joint guards, front and rear
DRIVELINES NEED TO BE PAINTED IN BRIGHT COLORS to be able to be located if dropped from vehicle
SAFETY
5 point harness
4 point roll cage and WINDOW NETS
Fire extinguisher, helmet, and racing fire suit required, pants and shirt
Must have a master kill switch on rear of vehicle for battery power
Driveline brake shielding highly recommended!
Minimum 3 working brakes required.
Pro Stock
TIRES
45” maximum DOT tires, cutting and grooving allowed
No paddle tires
ENGINE
Specialty race fuels, ethanol and methanol allowed, no nitrous or nitromethane allowed
Engine swaps allowed, corporate matching
Aluminum Blocks Allowed, no forced induction
Open headers allowed exiting up or down, not out the side
Aftermarket fuel injection and port fuel injections allowed
Multiple carbs allowed
Engine must be factory deck height and bore spacing
BODY
Body swaps allowed, no fiberglass bodies
Wheel wells must match factory frames +/-2 inches
Body must be completely intact
Fender well trimming to accommodate larger tires
Inner fender not required
Windshields required
Bedside skins only are allowed must have 2 operable doors unless open bodied
Cab interior, anything that can be unbolted or unscrewed may be removed (no cutting)
FRAME & SUSPENSION
Factory frames only, must maintain at least 2 original cross members and be factory width
Front axle tube may not be further ahead than the engine harmonic balancer
Engine must be set in stock factory frame location
4-link suspension allowed front and rear
2 drive shaft loops, front and rear required, loops must be made of substantial rigid material, no chains, cables, or etc
U-joint guards required
Engine and chassis must be corporate matching
May use aftermarket transmission
Must have transmission blanket or approved shield, must have flex plate guard.
Tow hooks required front and rear
DRIVELINES NEED TO BE PAINTED IN BRIGHT COLORS to be able to be located if dropped from vehicle
SAFETY
5-point harness, 4-point halo cage in cab
Must have chain guard both sides and top if chain drive
A kill switch is mandatory and must be connected to electric fuel pump, a tether switch is mandatory
SFI harmonic balancer of shield required
Must have fire suit, pants and shirt required
If running alcohol fuels, must have 3 layer fire suit, head sock, leather boots or racing shoes, and gloves
Window nets on driver’s side or wrist restraints
Fire extinguisher required and must be compatible with the fuel used.
Must have a master kill switch on rear of vehicle for battery power.
Driveline brake shielding highly recommended!
Fire Suppression System Highly Encouraged - Required in 2025
Pro Modified
TIRES
45” maximum DOT tires, cutting and grooving allowed
Paddle tires allowed
ENGINE
Engine must be factory deck height and bore spacing
Specialty race fuels, ethanol and methanol allowed, no nitromethane allowed
Aluminum Blocks Allowed, no forced induction
Engine swaps allowed, multiple carbs allowed
Aftermarket fuel injection and port injection allowed
Open headers allowed exiting up or down, not out to the side
Nitrous allowed on small block engines only
Limited to 2 (Two) Stages of Nitrous
BODY
Must have a body around driver - Tech discretion if necessary
Must have barrier between driver and radiator
Fiberglass bodies allowed
FRAME & SUSPENSION
2 drive shaft loops, front and rear required, loops must be made of substantial rigid construction, no chains, cables, or etc
U-joint guards required
Tube chassis allowed
Any suspension
Tow hooks required, front and rear
Engine can be in any location, front or rear of driver.
DRIVELINES NEED TO BE PAINTED IN BRIGHT COLORS to be able to be located if dropped from vehicle
SAFETY
A kill switch is mandatory and must be connected to an electric fuel pump, a tether switch is mandatory
5-point harness and 6-point roll cage
SFI harmonic balancer or shield required
Must have chain guard on top and sides if chain drive
Must have trans blanket or approved shield, must have a flex plate guard.
Must have at least 3 layer fire suit, full face helmet, head sock, fire retardant gloves, leather boots or race shoes
Window nets or wrist restraints required
Fire extinguisher required and must be compatible with the fuel used.
Must have a kill switch on rear of vehicle for battery power.
Driveline brake shielding highly recommended!
Fire Suppression System Highly Encouraged - Required in 2025
General Rules and Safety
AA
All trucks must race, as they are teched in. NO MODIFICATIONS AFTER THE TECH HAS SIGNED OFF! This includes but not limited to – ignition timing changes and or dropping exhaust systems.
TECH CLOSES ONE AND A HALF (1.5) HOURS PRIOR TO RACE START TIME. If you are late, you do not race. Only exceptions made are if you pre-register the day before or the morning of the race by calling the SDMRI President or Vice President.
All trucks must be ready to race when their class is called. Pay attention, stay with your truck and be ready.
ABSOLUTELY NO DRINKING OF ALCHOHOLIC BEVERAGES by the driver or the pit crew before or during the race event.
You must remove your wristband to drink in the stands and you will not be allowed in the pit area until the races are completely done.
TRUCKS DRIVEN IN AN UNSAFE MANNER AND/OR ANY UNSPORTSMANLIKE CONDUCT WILL BE GROUNDS FOR DISQUALIFICATION WITH NO REFUND. SECOND DISQUALIFICATION FOR UNSPORTSMANLIKE CONDUCT WILL BE GROUNDS FOR DISQUALIFICATION FOR THE SEASON.
Drivers are liable for any damages caused to the lighting system including sensors, cords and starting tree. This includes parts and labor.
No smoking while racing and no passengers allowed.
Four pit crew members per racing vehicle MAXIMUM. Pit crew must be 14 years of age or older.
All drivers and their pit crew are required to sign a disclaimer.
Drivers under the age of 18 must have a valid driver’s license and parental or guardian signature on the disclaimer.
Drivers must wear DOT APPROVED HELMETS in all classes.
Fire extinguishers required in all classes
Neutral safety switched required in all automatic equipped vehicles.
Steering, brakes, and tie rod ends will be checked to meet safety requirements.
ALL VEHICLES RACED WILL HAVE A FRONT AND A REAR BRAKE IN ALL CLASSES. MOUNTING OF DRIVE LINE BRAKES WILL BE REVIEWD BY TECH TO PROVE THAT THEY ARE SAFE.
Batteries must be securely fastened – no bungee cords. If in driver’s compartment, battery must be enclosed.
Vehicles must be set up so no part of the driver’s body is allowed to flop outside the vehicle’s compartment
All classes must use windows, nets, or safety straps to keep arms inside vehicle compartment
All trucks are subject to teardown or tubing by the SDMRI tech team at owner’s expense,
Any truck can be protested. To do this, any driver must present $500 to the Tech Committee who at this time will determine if a teardown is necessary.
If the Tech Team decides the disputed vehicle is legal, the $500 goes to the owner of the protested vehicle.
If the Tech Team decides the disputed vehicle is illegal, the $500 goes back to the driver who presented the protest.
If a vehicle is caught running illegally after teched in, they will be disqualified for the day with no refund, trophy, winnings, or points earned for the day.
Second disqualification for illegal racing will be grounds for disqualification for the remainder of the season.
Time limit for trucks to stage is two (2) minutes simultaneously. Once trucks are staged, if either truck loses stage or breaks our (RED LIGHTS) it will be considered a loss!
Trucks going out of bounds will be disqualified for that race, DECISION FINAL! If one truck causes another to go out of bounds, the truck that was forced out will be the winner.
All “on deck” trucks must be lined up within the designated area prior to the staged trucks leaving the starting line. If you are not in the designated “on deck” area after the current race begins you will forfeit the round. Tech and line personnel have final say on this ruling as it applies