(All measurements taken with car ready to race at ride height.)

Rules are subject to interpretation by the race organizer.

Sprint Cars

• General –
  9. Wheel base 9.5” minimum 11.5” maximum
  10. Width 10.25 maximum width
  11. Must have 4-wheel independent suspension
  12. Single speed transmission
  13. No direct drive transmission or straight axle cars
  14. No gyro or traction control
  15. 2-wheel drive and rear wheel drive only
  16. No front brakes allowed
• Cage – Sprint cars must have a scale appearing contemporary cage made out of rounded stock. The cage must be symmetrical left to right and mounted level to the chassis. Unrealistic shaped cages designed to exploit the rules below are not permitted.
  3. Maximum cage width at driver halo, down tubes, and top frame rail: 3.600".
  4. Maximum cage height 5.5" from top of chassis to top of cage at highest point. Rear “down tubes” must slant forward. 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.
  5. Chassis may not extend outside of the side panels by more than 1/4" on either side.
• Bumpers – A flat, curved or tubular front bumper (or combination of) must be used and may not be designed to direct air or create downforce.
  1. Maximum height of front bumper is 1.75” from the bottom of the lowest point of the chassis. Scale appearing side nerf bars must be used on both sides of the car (left side of nitro sprint is optional due to clearance needed for nitro exhaust). A scale appearing rear hoop style bumper must be used. Bumpers and nerf bars must be made of rounded stock with no sharp edges.
• Tail tank – A traditional scale appearing rounded style three dimensional rear fuel cell must be used.
• Headers - Three dimensional scale appearing exhaust headers must appear on both sides of car in “engine area”.
• Side panels – Flat side panels may be made from molded or fabricated polycarbonate.
  3. Maximum height of side panels in front of the driver cockpit is 3.80” from the bottom of the chassis. Must have minimum of 3/4" high by 2.5" long openings on both sides of cage in driver compartment. Additional material may be used/added to either side of the side panel openings to replicate a scale appearing driver but may not exceed 1" x 1". (Note that the top wing mounts may cover these openings for winged classes.)
  4. Side panels may not extend beyond the rear of the cage by more than 0.25”.
  5. Side panels may not extend above or in front of the front downtubes.
  6. Side Panels may not extend into the area that is behind the rear axle AND below the top of the rear nerf bar.
  7. Scale appearing driver arm guards and engine vents may be used but cannot extend more than 3/8" from the side panels. No other flares or turnouts designed to deflect, trap and/or form a pattern for air to travel in a directed manner are permitted except for those used to cool electronics.
• Hood Area – A scale appearing hood must be used and is defined as beginning at the front axle and ending at the front of the driver cockpit. The hood must be symmetrical from left to right. The hood must be tall enough and wide enough to allow room for a scale engine intake and air cleaners (no unrealistically low or flat hoods).
  1. Minimum vertical gap from top of hood to bottom of front cage crossbar: .750".
  2. The hood may not drop below the nearest point of the side panels by more than 3/8” and may not have any channels more than 0.25” deep designed to trap or direct air.
• Nose Area – A molded or fabricated nose piece may be used and is defined from the front axle forward to the front bumper.
  3. Front bumper may not extend more than 3” from front axles. Nose piece (any Lexan) must be at least ¼” back from the leading edge of the front bumper. Maximum width of nose piece/bumper is 3.75".
  4. Maximum width of any surface designed to add downforce is 3.125”.
  5. Nose piece may not extend above the cage downtubes or an imaginary line connecting the downtubes if the cage is a split design.
     • ***Note that the hood and nose piece can be one piece or multiple pieces for the purpose of easy access to electronics and suspension but are defined as above for purposes of aero rules.

• Front wing/mounts – For front wing dimensions see appropriate wing drawing pdf. The front wing center section may not extend in front of the front bumper.
  1. Front wing mounts may be made of Lexan but may not exceed 1.75” in length and 1.75” in height and may not extend in front of or behind the center section of the wing.
• Top wing/mounts –
  5. Top wing minimum height at leading edge: 5.00" from bottom of chassis.
  6. Top Wing maximum size 7”x7”.
  7. Top wing maximum height at leading edge: 6.50" from bottom of chassis. Center section and side panels must be made from at least 3 separate pieces of polycarbonate, carbon or aluminum material.
  8. All corners and edges must be rounded and free of sharp edges.
  9. Main and Front wings must be mounted so that they are centered on cage, no offset wings.
  10. Wing center sections must have all 4 corners set at 90 degree angles, no canted or angled panels.
  11. Wings must also be mounted level from side to side.
  12. Center section of wing may not extend beyond leading or trailing edge of side panels.
  13. Side panels must have braces that hold side panel rigid at 90deg. to center section during race conditions.
      1. 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.
      2. 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.

1. Flat foil center sections will be allowed a .250” turndown at the leading edge.

• Visors - A scale appearing visor may be used on any wingless sprint car. The visor must be flat and follow the contour of the front downtubes.
  1. No wider than the width of the downtubes where it is attached and no longer than 1".
  2. No additional 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.
• Tires-
  1. Buggy Tires:
     2. Any rubber 2.2 buggy tire
     3. 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.

• Minimum Weight
  1. 1616 grams
• Electronic Speed Control and Motor
  13. 5 class
      1. ROAR approved ESC Blinky zero timing
      2. ROAR Approved 13.5 motor
  14. Modified/Open
      1. ROAR approved ESC
      2. ROAR approved 10.5 or below

• Battery
  1. ROAR approved 2S Hard Case LiPo battery
  2. Maximum of 8.44 volts or less.

Late Models

• Bodies
  1. Any DODC approved body
  2. Molded portion of body can be no longer than 22”.
  3. Late Model bodies may have openings for cylinder head, fuel tank access, glow plug, engine tuning, and exhaust outlets only.
  4. An under body support may be added to brace each rear quarter panel, but must hold it in stock position, cannot be flared out.
  5. No additional wings, flaps, spoilers, wickers, vents or doohickeys will be allowed. Body may not be altered in any way from its stock configuration ie: shortened, lengthened, narrowed, flared fenders etc.
  6. Front and rear windows may be removed at trim lines but a flat Lexan or similar material deck must be added in cockpit area.
  7. Bodies with add on roofs may leave front and rear windows in or out but roofs must be mounted in stock position.
  8. All four wheel wells must be cut out to appropriate scale dimensions.
  9. Rear Spoiler
     2. Maximum chord from body deck including any wickerbills: 2.50"
     3. Rear Spoiler End Cap: See Drawing

• Maximum rear deck height from bottom of chassis is 4.0"

• Tires-
  1. Buggy Tires:
     2. Any rubber 2.2 buggy tire
     3. 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.

• Minimum Weight
  1. 1616 grams
• Electronic Speed Control and Motor
  1. Modified/Open
     1. ROAR approved ESC
     2. ROAR approved 10.5 or below

• Battery
  1. ROAR approved 2S Hard Case LiPo battery
  2. Maximum of 8.44 volts or less.

Mid-West Modified

• Basic Measurements
  9. Width: Min 9.25” / Max 10.50” (body must cover at least 7/8ths of both rear tires.)
  10. Length: Min 21” / Max 23” (measured at extreme ends of car)
  11. Front bumper must be mounted flat and cannot be angled up to act as a wing.
  12. Side windows must remain clear and can be cut out provided the cutout is flush with the center panel deck and a false cage or roof support is used to maintain the rigidity of the roof panel. Windows must also be the same on both sides.
  13. False Roll Cages must be mounted parallel with the side panels, cannot be thicker than .250, and may not be used to alter air flow in any way. False Roll Cages must be void of material in areas that do not mimic frame tubing, driver’s seat or helmet.
  14. Any bracing or supports used for the side panels or quarter panels must be a maximum of .750” wide and not be used to direct airflow.
  15. Additional wings, flaps, wickers, spoilers or other aero devices used to direct air are prohibited unless specified in these rules.
  16. Rear wheel openings must be to a minimum diameter of appropriate tire (3.25” for buggy tires) measured from the ground.
  17. Fabricated Bodies: Center panel, Hood, and Noses must be made from 0.030” thick polycarbonate material. Side Panels, Doors, Windows, Roof, can be made from minimum 0.020” thick polycarbonate material (measurements do not include any decal or wrap.)
  18. All Vacuum Formed body panels must be pulled from minimum 0.030” thick polycarbonate material.
  19. Bodies
      1. Center Panel (main inner center section panel)
         • Max Center Panel Width: 10.25” (measured as panel surface area inside the side panel mounting tabs.)
         • Must be the same width front and back.
         • Center Panel cannot extend past the side panels and must be flush with the back of the rear quarter panels.
         • Entire center panel must be flat (on one plane) from spoiler base to front edge of panel, terminating with a max .375” radius turn down or roll down featuring a minimum .500 lip (firewall) at a 90°°angle to the center panel.
         • Must be mounted parallel to bottom of chassis with maximum rake of .500” difference from leading edge of panel (before bend down) to trailing edge at spoiler base (measured from bottom of chassis).
         • No rear wheel cutouts are allowed on the horizontal plane of the center panel.
      2. Roof
         • Length: Min 4.5” / Max 6.5” Width: Min 6.0” / Max 7.5”
         • Roof Location: Min 2.5” / Max 3.5”
         • Front & Rear edges of roof must have bend down of Min .125” / Max .250” between 45° and 90° (no roof spoilers).
         • Clearance between center panel and top of roof: Min 1.50" / Max 2.25”
         • Max rake of .500" difference from leading edge to trailing edge measured from the center panel to top of roof panel.
         • Roof must be mounted square to the side panels.
         • Roof panel must be 90° at all (4) corners.
         • Roof panel cannot be dished.
         • Support fins, ribs, or any ridges may not extend higher than .125” over the plane of the roof panel.
         • Top of "A" pillar must terminate at front edge of roof.
         • Bottom of "A" pillar must terminate at the front edge of the side panel/door with a max height of .250” from top of side panel.

• Sail Panels
  • Sail panels cannot extend higher than the roof line or contain any sort of wicker or flaps, and must be the same shape and configuration on both sides
  • Sail panels must curve or angle down starting at no more than 1” behind the rear edge of the roof and end at a point no further back than .750” past the rear deck with a max height of 1.5” angled forward to meet at the corner of the deck.
  • Sail panels cannot end any further forward than 2” from the rear deck.
  • Sail panels can be bowed out, but cannot bow out past the plane of the side panels at large.
  • Sail panels can be cut out provided:
    • it does not affect the minimum range of the Side Panel template,
    • all remaining pillars and sail borders are a minimum .500"
    • normal rigid integrity of the roof and body is maintained thru inner supports and/or a false roll cage,
    • cut-out does not go below center panel deck.

1. Side Panels
   • Length: Min 12" / Max 14" (Measured at all points of the panel)
   • Height: Min 3” / Max 3.5” (Measured at all point of the panel)
   • Both sides must be symmetrical in length and mounting location (cannot be offset from each other).
   • Top of side panels must be flush to the plane of the center panel.
   • Leading edge of side panel can be angled back from the bottom to the pillar, but must be a straight edge. (no wheel cut outs)
   • Minimum distance between leading edge of side panel and back edge of front tire: .750” (measured with tire pointed forward and car sitting at resting ride height using a .750” block set down between the tire and panel as a no-go gauge)
   • Minimum distance from the center of the front axle back to the rear of the quarter panel: 15.75”. (** = be sure to leave room for front wheelbase and kick-up adjustments as well as different tire sizes for the min .750” gap)
   • Side panels can be flat or convex in shape (bowed out) as long as they fit within the overall max width, but cannot be concave in shape. “Step outs” at the bottom of panel are ok.
   • Side panels as well as rear quarter panels cannot be tucked under center deck panel.
2. Hood
   • Hood Length: Min 3" / Max 4.75" (Measured from the firewall to the point where the nose and hood meet)
   • Front of hood must be the same width as the Nose Panel. The hood must be flat and can taper out to the firewall but cannot cover front tires or exceed the width of the main deck panel. Max rake of .250" difference from leading edge to trailing edge measured from the bottom of the chassis.
   • The “engine area” of the hood cannot be enclosed. A max hood side panel of .750” is allowed, but cannot extend above the plane of the hood panel.
3. Nose
   • Nose Panel Width: Min 4" / Max 5.50" (Measured as panel surface area inside the end plates)
   • Nose Panel Length: Min 4" / Max 5.50" (Does not include a max allowable .500” mounting tab)
   • Nose panel must not be concave (dished) in shape or contain any ribs, wickers, flaps, or openings to direct airflow.
   • Side panels of Nose must be perpendicular to the nose panel (no flares). Allowable extension of side panels above the plane of the Nose Panel is maximum .250" at every point along the plane of the nose panel. A max .250” flare is allowed at the bottom of the Nose Side Panel

• Spoiler & End Caps
  • Spoiler max length: 1.5" including a max .250” wicker. Spoiler cannot be wider than center panel.
  • No more than (2) spoiler center braces allowed. Center braces can be no larger than optional spoiler end caps.
  • End Caps cannot extend past end of Side Panel by more than .750”. (Included in the Max Length of Body)
  • End Cap Size: Length 2.75" Height 1.5". Height is area of End Cap above the rear deck
• Tires-
  1. Buggy Tires:
     2. Any rubber 2.2 buggy tire and wheel
     3. 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.

• Minimum Weight
  1. 1616 grams
• Electronic Speed Control and Motor
  13. 5 class
      1. ROAR approved ESC Blinky zero timing
      2. ROAR Approved 13.5 motor
  14. Modified/Open
      1. ROAR approved ESC
      2. ROAR approved 10.5 or below

• Battery
  1. ROAR approved 2S Hard Case LiPo battery
  2. Maximum of 8.44 volts or less.

Bomber

• Chassis
  1. Must be rear motor 2wd short course chassis OEM plastic chassis (Traxxas LCG chassis allowed) (no carbon chassis)
  2. Traxxas or (manufacture specific) aluminum upgrades are allowed except for shock towers and arms
  3. RPM parts are allowed. Parts must be used as intended
  4. No adjustable rear arms
  5. Battery must be placed within the centerline of the chassis
  6. Electronics (RX/ESC/AMB) must be installed within chassis surface, no outside installation.
• Suspension
  1. Traxxas 2WD plastic shocks only (grey or black version) (fronts in front, rears in rear) Aluminum Traxxas Shock Cap Allowed.
  2. The shock’s travel may be shortened with internal shims (i.e. fuel tube or solid shims).
  3. All suspension parts (such as A-Arms) must remain in original positions it was designed for (no swapping left to right).
  4. Rear camber links must remain in original height position (upper hole on shock tower not allowed.
• Electronics
  17. Traxxas Titan 550 12T Brushed Motor (TRA3785), ROAR Legal 17.5 sensored brushless motor.
  18. Traxxas XL-5, Hobbywing Quicrun 1060 ESC allowed for brushed motors, Any ROAR approved brushless ESC in Blinky.
  19. Traxxas BL-2S (TRA3382)
• Battery
  1. ROAR approved 2S Hard Case LiPo battery
  2. 44V is the maximum charge.
• Tires
  1. Proline Hoosier G60
  2. Proline Hot Laps
  3. JConcepts Swiper
  4. DE Grooved G6T
  5. DE G6T SC
  6. Traxxas Slash designed tires
  7. Any tire additives that are used must be wiped clean from the tires before any races or practice sessions.

MudBoss

• Chassis
  1. Traxxas 2wd (LCG Chassis Allowed)
  2. Original MFG suspension and chassis parts only. Front bumper, right side bumper must be removed. Front body post brace can be retained as a (shock tower support). It must be cut to fit within hood width.
  3. Left side and rear bumpers can also be removed (if desired) **rear RPM bumper is allowed
  4. Traxxas front optional bumper (TRA2735) can be used. Must be (angle down) – Mandatory
  5. Major alterations to the chassis or modification to drivetrain/suspension components is not allowed
  6. Electronics (RX/ESC/AMB) must be installed within chassis surface, no outside installation.
  7. Battery brace can be trimmed to allow different LiPo battery wire Configuration
• Electronics
  17. Traxxas Titan 550 12T Brushed Motor (TRA3785), ROAR Legal 17.5 sensored brushless motor.
  18. Traxxas XL-5, Hobbywing Quicrun 1060 ESC allowed for brushed motors, Any ROAR approved brushless ESC in Blinky
  19. Traxxas BL-2S (TRA3382)
• Battery
  1. ROAR approved 2S Hard Case LiPo battery with a maximum of 5800mah and 50c full size stick pack with connector
  2. 44V is the maximum charge!
• Adjustment
  1. Traxxas spur gears of 76/83/86/90 (ONLY) with all transmission parts in place including slipper clutches and pieces.
  2. Any pinion size is allowed.
  3. No modifications can be made to the transmission’s case (i.e. to allow a biggest gear ratio).
  4. The rear differential may not be modified or locked in any way. The differential must have normal diff action and cannot turn the motor over when rotating one rear tire against the normal resistance of the motor.
  5. You must run the OEM Slash Transmission that comes out of the kit. Aftermarket slipper lockouts or eliminators in NOT ALLOWED!
  6. The Proline Pro Series 32P Transmission is not legal for MuddBoss!.
  7. You are allowed to use any original wheel spacer combination (Black, Grey or any combination of both types).
  8. Transmission functionality rule (motor cannot spin while turning slowly one rear wheel a full turn).
  9. Traxxas Slash *Steel* transmission gears only (internal plastic transmission gears not allowed).
• Suspension
  1. Traxxas 2WD plastic shocks only (grey or black version) (fronts in front, rears in rear) Aluminum Traxxas Shock Cap Allowed or Traxxas GTR Shocks Allowed.
  2. The shock’s travel may be shortened with internal shims (i.e. fuel tube or solid shims). Stock Traxxas Springs only (cutting of springs are allowed).
  3. All suspension parts (such as A-Arms) must remain in original positions it was designed for (no swapping left to right).
  4. Rear camber links must remain in original height position (upper hole on shock tower not allowed.
• Tires
  1. Any original Traxxas Slash rubber tire/wheel/inserts (BFG/KUMHO/SPEC) any wheel combination of the SAME TIRE TYPE (i.e. 4 fronts, 4 rear, 3 fronts, 1 rear) “S1” compound*is (Allowed).
  2. Traxxas Slash “SPEC” rubber tire/wheel/inserts only, any wheel combination of those (ie..4 fronts, 4 rears, 3 front, 1 rear…)(part# TRA5863-64-71-73-75) “S1” compound IS (Allowed).
  3. Any tire additives that are used must be wiped clean from the tires before any races or practice sessions.
     
     
• **Anything not mentioned in the above rules will not be allowed or must be approved beforehand**

SR10 Spec Class

• Shocks & Suspension
  1. Must run stock shock bodies and caps
  2. Changing shock oil in each of the shocks is allowed
  3. Must run stock 12mm shock piston, 2-hole, Part No.91444
  4. Limiters in the shocks are allowed
  5. Pre-load and droop may be adjusted
  6. Aftermarket springs are allowed
• Transmission Gearing & Differential
  1. Spur gear must be 87T , Part No.9654 pinion gear must be no higher than 24T
  2. Differential, when turning one back tire, opposite wheel must not turn in the same direction, holding off ground. Fluid may be adjusted.
  3. No aftermarket upgrades to the drivetrain are allowed, MUST BE ALL Stock SR10 components
  4. Must run stock slipper clutch assembly, no lockouts
• Electronics – Motors, ESC, Servo & Radio
  1. Electronics must be mounted in stock OEM location
  2. No AVC, GYRO or additional traction control devices allowed (Automatic DQ)
  3. Motor 3300Kv Reedy from Team Associated is the only motor allowed
  4. No motor Cooling Fan
  5. ESC must be Reedy SC600-BL Brushless ESC or Hobbywing Max10 Sensorless ESC
• Batteries
  1. ROAR approved 2S Hard Case LiPo battery
  2. Maximum of 8.44 volts or less.
  3. Battery must be mounted down the center of the chassis or in OEM location
• Body Style
  10. Molded SR10 Monte Carlo body or approved bodies noted below are the only allowed bodies in SR10.
  11. No additional wings, flaps, wickers, vents or air devices allowed (no added holes)
  12. You may have a total of 1” spoiler including the molded spoiler
  13. Spoiler may not be wider than the stock molded spoiler
  14. Decking is not allowed, must have all windows and no cut outs of any window
  15. Body must be cut to trim lines; No cutting out of the back above bottom of bumper, fender wells can be cut for tire clearance
  16. Approved Body list:
      1. SR10 Street Stock Body, Clear (paint/wrap as wanted) Part No. 784695711921
      2. SR10 Street Stock Body, Clear (Painted) Part No. 784695711938

• JCONCEPTS 1978 Camaro Street Stock Body – Part No. 0395

1. JCONCEPTS 1987 Monte Carlo Street Stock Body – Part No. 0422L

• Tires & Wheels
  1. Rubber Tires & 1/10th Buggy Tires & Wheels Only
  2. You may run the stock SR10 rear and front tires
  3. SR10 Wheels Stock Wheels are allowed
  4. Any tire additives that are used must be wiped clean from the tires before any races or practice sessions.

21.5 Street Stock

• Chassis
  1. 1/10 buggy chassis
  2. No adjustable rear arms
  3. No additional weight outside of chassis
• Electronic Speed Control and Motor
  21. 5 class
      1. ROAR approved ESC Blinky zero timing
      2. ROAR Approved 21.5 motor

• Battery
  1. ROAR approved 2S Hard Case LiPo battery
  2. Maximum of 8.44 volts or less.
• Body
  1. 1 inch max Rear Wing with no side dams
  2. Must have rear bumper on body
  3. Race numbers are encouraged
• Tires
  1. Buggy Tires:
     2. Any rubber 2.2 buggy tire
     3. 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.

10.5 Street Stock

• Chassis
  1. 1/10 buggy chassis
  2. No adjustable rear arms
  3. No additional weight outside of chassis
• Electronic Speed Control and Motor
  1. ROAR approved ESC
  2. ROAR Approved 10.5 motor
• Battery
  1. ROAR approved 2S Hard Case LiPo battery
  2. Maximum of 8.44 volts or less.
• Body
  1. 1 inch max Rear Wing with no side dams
  2. Must have rear bumper on body
  3. Race numbers are encouraged
• Tires
  1. Buggy Tires:
     2. Any rubber 2.2 buggy tire
     3. 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.

SC B-Mod

• Chassis
  1. 1/10 2wd SC chassis (no carbon chassis)
  2. No adjustable rear arms
• Electronic Speed Control and Motor
  1. ROAR approved ESC
  2. ROAR Approved 10.5 motor
• Battery
  1. ROAR approved 2S Hard Case LiPo battery
  2. Maximum of 8.44 volts or less.
• Body
  1. 1 inch max Rear Wing with no side dams
  2. Must have rear bumper on body
  3. Race numbers are encouraged
• Tires
  1. SCT Tires:
     1. Any rubber SCT Tire allowed
     2. 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.