DirtOval.com National Rulebook
All content subject to change.
All Changes to this edition in RED
As a primary safety requirement all tracks utilizing DODC rules must have an adequate number of fire extinguishers on hand for all events whether they be nitro or electric.
The following rules are suggested guidelines referring to race procedures and formats. It is understood that some tracks and or events may alter these procedures to suit there racers or programs and in particular for special events.
- All qualifiers and mains should be 4 minutes in length, qualifiers should use Ifmar starts.
- Turn marshals should not work on or repair cars. Minor issues like popping on a ball cup for a steering link is ok.
- If a pit lane is available cars must enter and exit the racing surface via the pit lane at all times.
- Any cars damaged and placed in the infield will remain there until that race is over.
- All drivers must turn marshal the race immediately following their race.
- All cars will be made available for tech inspection before and after race if required by race director.
- Once a car has gone through pre-race tech it must go directly to track not back to pit area.
- All racers must have a personal transponder if required by the race organizer.
Race directors will have ultimate authority over rules enforcement. The primary basis for any rules decision must be based on what will be best for the majority of racers. If an item is not addressed in the rules listed here than you should assume it is not legal.
1/10th Scale Rules
The following rules are to be used for governing all applicable 1/10th scale classes. The rules are divided into the following categories:
Chassis: 2wd and 4wd
Power: Electric (Motor:Mod, Stock, Spec Speed Control: Open, Sportsman, Spec)and Gas (Limited, Nitro)
Body: Sprint, Latemodel and Dirt Modifed
When determining the rules or classes you intend to use the above list should be treated like a menu. You would pick one option from each category and then an option from either the electric or nitro subcategories for the type of power you intend to use for the given class. In order for a class to be considered a DODC legal class it must fit somehere within all of the above options.
General: For turn marshal safety all cars must have a front bumper that is made of a shock absorbing material e.g. nylon, delrin, plastic, kydex etc. Front bumpers must be mounted in such a way that they will contact an object prior to any other portion of the car in a front impact. All cars must have 4-wheel independent suspension, single speed transmissions only. No Gyros of anykind are allowed. All power, radio equipment and weights must be in a secured and fixed position and not moveable during a race.
Tires: Tire choices will be determined by track surface and race organizers. General tire choices will be between either foam tires or rubber tires however a race director may implement a SPEC tire rule if desired. Track owners may restrict tire additives at their discretion. Any tire additives that are used must be wiped clean from the tires before any races or practice sessions. No silicone capped or impregnated tires or rubber capped foam tires allowed.
- Foam Tires:
Max wheel diameter: 2.0”
Front tire and wheel width: Max 1.1”
Rear tire and wheel width: Max 1.5”, Min 1.4"
- Rubber Tires:
Max wheel diameter: 2.2” front and rear
Max wheel width: 1.750” rear, 1.000” front
Max tire width: 1.850” rear, 1.250” front
2WD Chassis: All entries must be 2wd and rear wheel drive only. No straight axle cars are allowed. No front brakes allowed.
- Wheelbase: 9.5” min, 11.5" max
- Maximum width: 10.000” (foam tires), 10.250" (rubber tires)
Electric Minimum Weights
Foam Tires: EDM, LM = 53.0oz, Sprint = 55.0 oz
Rubber Tires: EDM, LM 55.0oz, Sprint = 57.0oz
Nitro Minimum Weights
Foam Tires: EDM, LM, SPRINT = 56.0 oz (WITH FUEL)
Rubber Tires: EDM, LM, Sprint 58.0 oz. (WITH FUEL)
4WD Chassis: All entries must be 4wd drive only. No 2wd cars allowed and all components of drivetrain must be in place and enabled to drive all 4 wheels of the vehicle. Drivetrains must be either Chain, Belt or Shaft driven. Ball or gear differentials, and or spools are legal front or rear. One-way bearings are only legal on front drivetrain, outdrives or axles. Front and rear Drive ratios must be the same, no overdriving either end of the drivetrain.
- Wheelbase: 10.000” min, 11.500" max
- Minimum width: 9.0", Maximum width: 10.250"
- Must use REAR tires and wheels on all four corners
Electric Minimum Weights
Foam Tires: 62.0 oz
Rubber Tires: 64.0 oz
Motors & Batteries
The following options define the electric classes that are available under DODC Rules.
- 17.5 Spec: Novak Ballistic, Premium Ballistic, High RPM Ballistic and Vulcan Spec 17.5 motors only. Any parts standard to any of the listed motors can be used including, ceramic bearings and vented endbells. All motors may use the 12.5mm that comes standard in the Vulcan Spec Motor. Sintered rotors only (no SmCo rotors). No parts of motors may be modified, altered or removed in any way.
DODC SPEC SS motors are no longer legal.
- 13.5 Spec: Novak Ballistic, Premium Ballistic, High RPM Ballistic and Vulcan Spec 17.5 motors only. Any parts standard to any of the listed motors can be used including, ceramic bearings and vented endbells. All motors may use the 12.5mm that comes standard in the Vulcan Spec Motor. Sintered rotors only (no SmCo rotors). No parts of motors may be modified, altered or removed in any way.
DODC SPEC SS motors are no longer legal.
Spec Class Batteries:
The following batteries are the only batteries legal for use in DODC SPEC Classes.
DODC SPEC 3200 28C
RC King 5200 30C
LiPo Onyx 2S 7.4V 4000mAh 25C Hard Case Deans
LiPo Onyx 2S 7.4V 5000mAh 25C Hard Case Deans
Dynamite DYN9005EC Reaction 5000mah 2S 30C
Dynamite 5302D Speedpack Gold 4200mAh 2S 30C(still legal but no longer available)
Batteries must use stock Deans style plug for connection to ESC. No additional batteries are allowed including those used to power recievers or cooling fans.
- 17.5 Stock: Any Motor from the ROAR Approved Stock/17.5 Spec category (D3.5 Motor legality at race directors discrestion until 3/30/14) and any ROAR approved 7.4 Volt 2 cell Lipo battery are legal. Batteries must use a quick release hobby grade connector for connection to the ESC ie:sermos, deans, traxxas etc. No additional batteries are allowed including those used to power recievers or cooling fans.
- 13.5 Stock: Any Motor from the ROAR Approved Modified/13.5 Spec category and any ROAR approved 7.4 Volt 2 cell Lipo battery are legal. Batteries must use a quick release hobby grade connector for connection to the ESC ie:sermos, deans, traxxas etc. No additional batteries are allowed including those used to power recievers or cooling fans.
- Modified: Any motor from the ROAR Approved Modified or Stock category and any ROAR approved 7.4 Volt 2 cell Lipo battery are legal. Batteries must use a quick release hobby grade connector for connection to the ESC ie:sermos, deans, traxxas etc. Race organizers may impose a minimum turn limit at their discretion ie: 6.5, 8.5, 10.5 etc.
All racers shall take every precaution to insure safe charging and discharging techniques with their batteries. This shall include but is not limited to, attentive monitoring of battery during charging and use of a proper charging container i.e., LiPo sack. To ensure safe charging methods are followed by all competitors, all batteries may be checked prior to each race to ensure battery voltage is a maximum of 8.44 volts or less. If the battery reads 8.45 or more you do not race. Battery temperature may also be checked with the following pre-race procedure. A control pack will be placed in the tech area for the purpose of monitoring the pack temperature. Checked batteries shall be no more than 10° F above the temp of the control pack.
The following options for Electronic speed control rules are available under the DODC electric classes. When choosing an electric class of competition the speed control used for that class must be defined by one of the following three options.
- Open Speed Control/ Open Timing. Any production ESC with an average street price of no more than $250.00 is legal in this class. There are no restrictions on timing profiles for these ESC's. Must be available thru normal hobby distribution channels.
- ROAR Approved Sportsman ESC's. (BLINKY MODE) Any Speed Control from the ROAR Approved Sprotsman ESC list with an average street price of no more than $250.00: ROAR APPROVED SPORTSMAN ESC's Speed controls in this class must be run in the mode specified on the ROAR page. .
- SPEC SPEED CONTROL: ANY Speed control or speed controls, may be designated as a SPEC Speed control for any given class that a track owner or race promotor chooses.
All classes: Maximum fuel tank size is 75cc. No stinger modifications and no pipes with adjustable stingers or any moving parts are allowed.
- Limited: O.S. Max 12TG and TG2 Production motors only. Must be out of the box STOCK. No modifications allowed. Rotary or Slide carb version ok. Any glow plug may be used. Glow plug gasket/washers of any size are permitted but not required. Production headers and pipes only with max 6mm stinger opening. NO NARROWED FLYWHEELS ALLOWED.
- Nitro: Any .12 cubic inch engine are legal. Un-modified .15 Rtr engines may be used but must utilize stock pullstart or rotostart system. NO NARROWED FLYWHEELS ALLOWED.
All Latemodels, Dirt Modifieds and Sprint car bodies and cages must resemble contemporary full scale cars racing in “World of Outlaws” and “DIRT” sanctioned events. All corners of bodies and wings must be rounded for safety.
All height measurements are from bottom of chassis unless otherwise noted.
The only bodies legal for the Late Model class are those that have been approved by DirtOval.com and are listed on the DirtOval.com Aprroved Late Model body list. Any manufacturer who would like to have a body approved may contact DirtOval.com for approval specifications and instructions. Molded portion of body can be no longer than 22”. Approved body lists will be amended on APRIL 1st and OCTOBER 1st of each year.
Late Model bodies may have openings for cylinder head, fuel tank access, glow plug, engine tuning, and exhaust outlets only. An under body support may be added to brace each rear quarter panel, but must hold it in stock position, can not be flared out. No additional wings, flaps, spoilers, wickers, vents or doohickeys will be allowed. Body may not be altered in any way from it’s stock configuration ie: shortened, lengthened, narrowed, flared fenders etc. Front and rear windows may be removed at trim lines but a flat lexan or similar material deck must be added in cockpit area. Bodies with add on roofs may leave front and rear windows in or out but roofs must be mounted in stock position. All four wheel wells must be cut out to appropriate scale dimensions.
- Rear Spoiler: maximum chord from body deck including any wickerbills:
2.00" for Foam Tire
2.50" for Rubber Tire
- Rear Spoiler Cap: See Drawing
- Maximum rear deck height from bottom of chassis is 4.0"
Approved Late Model Body List : Effective: 10/01/12 thru 03/31/13
- Custom Works #9012 Eldora Late Model (10.0")
- Custom Works #9015 Springfield Late Model (10.0")
- Custom Works #9016 Paducah 2 Late Model (10.0")
- Custom Works #9070 Keystone Late Model (9.0")
- Custom Works #9071 Buckeye Late Model (9.5")
- Custom Works #9072 Mountaineer Late Model (10.0")
- McAllister #207 Tulsa Late Model
- McAllister #250 Vegas Late Model
- McAllister #252 Winchester Late Model
- McAllsiter #237 Bakersfield Late Model
- BMS Racing #P103 Shadow
- Factory Works #7353 Rocket Late Model
- Factory Works #7357 Concord Late Model
- C&M Bodies #2010 Volunteer Late Model
- C&M Bodies #2010-003 Nightmare Late Model
- C&M Bodies #2011-001 Volunteer 10"
- C&M Bodies #2011-002 Nightmare HD 9.5"
- Stalker Bodies #009 Sniper 9 Late Model
- Stalker Bodies #010 Sniper Late Model
- Stalker Bodies #011 Specter 9.5
- Stalker Bodies #012 Specter 10
- Stalker Bodies Specter 9.0
- Protoform #1234-21 Cyclone 9.5 Late Model
- Protoform #1235-21 Cyclone 10.0 Late Model
Must have scale appearing cage, hood, side panels, fuel cell, nerf bars and front and rear bumpers. All cage and body components such as cage, bumpers, nerf bars, hoods, side panels, tanks, etc. must be mounted on the centerline of the cage. Chassis may not extend outside of the side panels by more than 1/4" on either side. All electronics, radio gear, fuel tanks, transmissions and gears must be positioned inside the cage side frames. Three dimensional scale appearing exhaust headers must appear on both sides of car in “engine area” (left side of nitro sprint is optional). Rear cage side panels may be used but may not extend beyond cage frame more than .250". No lexan or any other material may be mounted to nerf bars, bumpers, cage, wing or any other part of the car that will trap, alter, or direct air flow for the purpose of gaining an aerodynamic advantage. Must have appropriate openings on both sides of cage in driver compartment, forward portion of side panels can be no taller than highest point of hood. Additional material may be used/added to either side of the side panel openings to replicate a scale appearing driver but a decal or image of driver must appear on this additional material.
- Maximum Length: 18.000"
- Maximum width of hood: 3.600"
- Maximum Chassis width: 4.025"
- Maximum cage width at driver halo, down tubes, and top frame rail: 3.600"
- Maximum cage height 5.5" from top of chassis to top of cage at highest point
- Minimum vertical gap from top of hood to bottom of front cage crossbar: .750"
- Wing minimum height at leading edge: 5.000" from bottom of chassis
Wings: Center section and side panels must be made from at least 3 separate pieces of polycarbonate, carbon or aluminum material. All corners and edges must be rounded and free of sharp edges. Main and Front wings must be mounted so that they are centered on cage, no offset wings. Wing center sections must have all 4 corners set at 90 degree angles, no canted or angled panels. Wings must also be mounted level from side to side. Center section of wing may not extend beyond leading or trailing edge of side panels. Side panels must have braces that hold side panel rigid at 90deg. to center section during race conditions. Two braces are required from top of the center foil to the left sideboard and one brace is permitted below the center foil to the right side board. Braces can be a maximum of .750" wide and front edge of front brace must be no more than 1.5” back from side panel leading edge. Side Panels may have front, back, top and bottom turnouts of no more than .375" and are included in max dimension. Flat foil center sections will be allowed a .250” turndown at the leading edge.
The 6x6" wing will be the standard Sprint Car wing size. Race organizers and series directors may at their discretion allow the optional 7x7" wing rule for races and series using buggy or rubber tires.
Top wings are mandatory and front wings are optional for all sprint classes. Race organizers may also choose to run wingless sprint classes at their discretion where top and front wings are not allowed.
6x6" Foam Tire Wing: See Drawing
7x7" Buggy Tire Wing: See Drawing
Top wing mount can not exceed the dimensions of the following template: SEE DRAWING
Dirt Modified (OLD STYLE)
Inner panel must have hood that extends from front of inner panel to at least the leading edge of the roof. Front bumper must be mounted flat and can not be angled up to act as a wing. An additional front body panel is allowed on the front of the car but may not extend forward of the front bumper. Front and rear windows must be removed and any clear portion is included in max roof length dimension. Side windows and A pillars must attach to side panels at top edge of door and must also contact entire length of roof (i.e. no large gaps between roof and top of windows, no T-tops). Roof width must be at least .500" narrower than inner panel max width dimension. Side windows must remain clear and no portions of side window may overlap side or sail panel. As an alternative side window material may be removed but A pillar must still remain in tact from front of door to front of Roof. Roof, windows, side and sail panels must be symmetrical. Front edge of Door/side panel may not extend past the centerline of the front axle with wheels straight. Front of sail panel may be no more than 1” forward of rear tire leading edge and can not overlap side windows. No additional lips or flaps are allowed with the exception of a .250" bend at top and bottom of side and sail panel. Reasonable size and quantities of braces are allowed if desired. Bodies must have at least 1/3 of right rear tire exposed when viewed from front, top and rear of car. No rear wheel cutouts are allowed on the horizontal plane of the inner panel.
- Maximum length: 22.000"
- Maximum width of inner panel: 8.000"
- Minimum hood width: 2.000"
- Minimum hood height: .750"
- Maximum front bumper width: 5.000"
- Front body panel max width: 4.500"
- Front body panel max chord length: 3.500"
- Max roof width: 7.000"
- Minimum roof height: 5.000" from bottom of chassis
- Maximum height of body at highest point: 7.000" from bottom of chassis
- Maximum roof length: 6.500" plus additional .500” rear spoiler allowed on roof
- Maximum side panel length: 17.000"
- Rear spoiler: max chord is 3.125" from body deck including any wickerbills
Dirt Modified (NEW STYLE)
Front bumper must be mounted flat and can not be angled up to act as a wing. An additional front body panel is allowed on the front of the car but may not extend forward of the front bumper. Front and rear windows must be removed and any clear portion is included in max roof length dimension. Side windows must remain clear. No rear wheel cutouts are allowed on the horizontal plane of the inner. Right and Left rear wheel wells must be cut out to appropriate scale dimensions.
Dimensional specifications Drawing: EDM SPECIFICATIONS
- Must have 2 side panel braces as specified in drawing that must hold side panels at 90 degrees to inner panel both staticly and during racing conditions.
Roof specifications Drawing: Roof Specifications
- Must have rear roof spoiler Min 1/8" Max 1/4" bend DOWN between 45 and 90 degrees
Side panels must be no larger than one of the following three templates:
Bicknell Template Teo Template Troyer Template FULLSIZE TEMPLATES
- All fabricated body panels ie: Doors, Windows, Roof, and Inner Panel must be made from minimum .020" thick lexan/polycarbonate material (.020" measurment does not include any decal or wrap)
- All Vacuum formed body panels must be pulled from minimum .030" thick lexan/polycarbonate material. Separate hoods and front body panels may be pulled from .020" lexan/polycarbonate material.
- Inner panel and spoiler can not extend beyond rear of side panels
- Outer front edge of inner panel can not extend beyond the front of the door but may taper from that point forward of the door toward the hood at a point no more then 1.5" forward of the door.
- Inner panel must be flat (on 1 plane) from spoiler base to a point within 1.5" from front of door.
- Maximum length of complete car: 19.5"
- Both sides of body must be at 90 Degrees to the rear of body and or spoiler
- Door/side panel may have a 90 degree "BEND IN" max 3/8" at bottom for strength
- Maximum front bumper width: 5.0"
- Front body panel max width: 4.0"
- Front body panel max chord length: 3.00"
- Max Side lip on front panel and Hood 1/4"
- Rear spoiler: max chord is 3.0" from body deck including any wickerbills
- Left Side Panel must be inside a straight line drawn from the outside of both left side wheels/tires and outside of left side of chassis.
- Bodies must have at least 1/3 of right rear tire exposed when viewed from front, top and rear of car.
Inner panel must have SCALE APPEARING hood that extends from at least the door leading edge to at least the leading edge of the roof. The following specifications are relative to the hood in the area defined in previous sentence.
- Hood must be centered on inner panel
- Hood Width: Minimum 2.5"
- Minimum hood height for entire length is: .750"
- Clearance between top of hood and leading edge of roof is min. 1.0" and max 2.0"
Mid-West Dirt Modified
At the request of the rubber tire racers across the midwest, here are the DirtOval.com 1/10 (Rubber Tire) "Midwest" Modified class Body Rules to go into effect for 2015. This class should not be confused with the "M1" modified class some foam tire tracks have recently adopted.
We had hoped to have these posted much sooner, and we apologize for the delay. There really isn't an excuse for being so late other than most of the delay is due to the dedication from everyone involved to get this as good as possible from the start. We would like to thank: Zack Harrison, Adam Sippel, Phil Beardshear, Ed Bogaard, and Doug Gaut for their input and assistance throughout this whole process.
Full Rules in PDF format available here: DODC Midwest Modified Rules