2024 4 CYLINDER RULES

Updated December 3rd 2023

Safety

  • Snell approved racing helmet within 5 years of manufacture date. (No motorcycle or DOT helmets.) SA2015+ Certification Recommended.
  • Full fire suit, gloves, and shoes made for racing.
  • Neck Rolls – OK
  • Head and neck restraint recommended.
  • Must have a fire extinguisher located within reach of driver.
  • Racing harness with up to date SFI rating is mandatory. Mounted in a safe manner to the cage.
  • Racing Seat and window net mandatory, both mounted solidly to the roll cage. Full containment seat recommended.

Roll cage 

  • Minimum of 4 point cage is mandatory, 6+ point cage suggested.
  • Minimum of three (3) Horizontal driver side door bars with a 24”x30”x1/8” steel plate mandatory.
  • Roll cage tubing will be 1-1/2”+ dia. X .095+ sidewall round tubing.
  • Must run at least 3 bars in front of driver; min 3/8” solid round bar.
  • May run two (2) down bars to the front strut towers for stiffening.
  • May run two (2) down bars to the rear strut towers for stiffening.
  • May run strut tower side to side cross braces. 
  • Roll cage tubing connections MUST be welded around the entirety of each joint. Including on top of cage.

Chassis & Body 

  • Any front wheel drive OR REAR WHEEL DRIVE four-cylinder cars. No convertibles or AWD cars will be allowed. 4cyl Trucks allowed, no SUV’s. 4cyl Trucks must retain tailgates. 
  • Wheelbase may be no shorter than original OEM specifications. Rear steer is allowed.
  • Doors must be welded or chained closed.
  • All OEM metal bumpers must be strapped or chained.
  • Must have tow chains at front and rear of car.
  • Radiator protection is Allowed.
  • All glass MUST be removed.
  • All flammable interior materials must be removed.
  • All exterior trim must be removed.
  • No rear-view mirrors.
  • Aftermarket style nose/tail pieces allowed. Any nose/tail piece used must be conformed to fit at reasonable and near-factory dimensions.
  • Aftermarket side skirts allowed. Aluminum skirts allowed.
  • No push bars to extend outside of bumpers or beyond nose piece.
  • All bumpers (stock or tubing) must be covered, no sharp edges may be exposed.
  • Sunroofs must be closed / covered with sheet metal.
  • Holes in firewall and floor should be covered in order to seal off driver from hot fluids or parts.
  • Stock firewall, front and rear.
  • Floor pans and/or firewalls should remain intact between the front strut towers and rear strut Firewalls and floor pans may be patched with STEEL for REPAIRS only.
  • Driver and front passenger door window openings along with rear and front window openings must remain open and uncovered (No Polycarbonate/Lexan Windows.)
  • Front windshield visors allowed, no more than 8” in height.
  • Passenger side window visors allowed, no more than 4” in height and must run horizontal.
  • Small rear side windows can be closed or covered.
  • No fins, wings, flaps or lips are allowed anywhere on body, apart from a stock spoiler.
  • Rear window louvers allowed.
  • Sheet metal decking, if installed, should remain flush with doors and stock body lines and should not create any lips, “Drop Decks” or airfoils.
  • Decking shrouds/rock guards no taller than 4.5” encompassing the driver for protection are allowed.
  • Factory OEM Hood or Similar reproduction for original make and model required.
  • Factory OEM Roof  for original make and model required to remain intact.
  • Factory OEM Roof Pillars for original make and model required to remain intact.
  • Any modifications or additions to OEM roof, pillars, or hood must also closely resemble the factory shape and body lines.
  • “Trunk Lids” and rear hatches must remain on the vehicle. Fabricated rear “Deck Lids” will be allowed but must resemble and maintain similar appearance to OEM.
  • Hoods, trunks, and deck lids will be secured with quick release latches or hood pins.

  • Some sheet metal will be allowed… The spirit of these rules is to keep cars remaining as close to stock appearing as possible. 

Weight 

  • 2,200 lbs. minimum weight with driver AFTER the race.
  • All added weight will be lead and painted white with your number clearly on it.

Gas Tank 

  • If stock gas tank is in front of the rear axle it may remain. Must have a skid plate. 
  • If stock gas tank is behind the rear axle, it must be replaced with a fuel cell located in the trunk. Minimum of four straps holding it in place and rear firewall must be enclosed.

Drivetrain 

  • Cars will use OEM four cylinder engine and transmission for make of car. (i.e.; GM-GM, Dodge-Dodge, Honda-Honda) 
  • Locked differentials are ALLOWED
  • No turbocharged, supercharged, multi-carbureted, rotary, or Cosworth engines.
  • Factory fuel injection or 2 barrel carburetor only.
  • Aftermarket/reprogrammed ECU/PCM ok.
  • Aftermarket/Milled throttle bodies ok. No Multiple TB or Velocity stack style.
  • Battery may be relocated. Must be in a waterproof box securely mounted.
  • No Nitrous
  • Gas Fuel Only, no methanal (Alcohol)

Suspension

  • Camber: RF – No Limit, RR – 1”, Left side will remain stock. 
  • Stock and aftermarket coil-overs ok. 
  • May run aftermarket sway bars. 
  • Spring rubbers ok. 
  • All suspension components will mount in the stock locations for the chassis.

Tires

  • Single side wall radial 300+ tread wear DOT tires maximum rating. No Z rated or better. 
  • No bias-ply, trailer tires, or recap tires.

Wheels

  • Stock or racing wheels ok. 
  • Maximum 7” wide. 
  • Beadlock on RF ok. 
  • Any offset on right side ok. 
  • 3” offset on left side ok. 
  • 1” safety lug nuts recommended. 

Every car will tech at the scale before the drivers meeting. If not legal per the techs discretion you will have until your heat race to fix the problem and have it checked once more. If it cannot be fixed at the Speedway you will not be able to run that nights events.