Limited Late Model
download and printing - Limited Late Model Rules
- Rules apply at all times car is on track. Snell-rated SA2000, SA2005, or SA2010 helmet required. Roll bar padding required in driver compartment (Fire retardant recommended). SFI-approved full fire suit required. Fire retardant gloves, shoes and neck brace (or head and neck restraint) required.
- Right and left seat head supports required if using head restraint system with no neck collar. Recommended: Fire retardant head sock and underwear.
- Driver-side window net required, minimum 16 inch by 20 inch ribbon or mesh style, and must be mounted to roll cage so latch is at top front of window. May also use strap triangle net.
- Minimum three inch (two-inch with head restraint system) wide SFI-approved five point safety belt assembly required (Y-type shoulder harness not allowed), must be mounted securely to roll cage, and must be no more than three years old. Kill switch required within easy reach of driver and must be clearly marked “OFF” and “ON”.
- It is recommended that each racecar have built-in fire extinguishing equipment, but cannot be of the dry powder type (must be Halon 1211 or equivalent).
- Drivers should have in their pit area as part of their equipment, at all times, a fully charged dry chemical, Halon (or its equivalent) fire extinguisher. Ten (10) or thirteen (13) pound fire extinguishers are highly recommended.
- All frames must be 2” x 2” square tubing or minimum 1.750” round tubing and must be a minimum 0.083” thick. No aluminum or any other soft metals. Minimum 103” maximum 112” wheelbase.
- Must have bumpers front and rear. No exterior front bumpers allowed. Rear bumpers must not extend more than 6” rear of body and no wider than the centerline of the rear tires. All bumpers must be bent and capped.
- Engine setback will be 6” from center of top ball joint to the #1 spark plug with a 1” tolerance on engine setback. There will be a 50lb penalty forward of the midplate for each 0.5” of set back beyond the 7”. Cars with more than an 8” engine setback will not be allowed to compete.
- Must have a 360 degree driveshaft loop no more than 6” behind the front u-joint. Must be minimum 0.250” x 2 “ steel or 1” tubing.
- All racecars must have a safe and professionally built roll cage. Cage must be a minimum 1.5” x 0.083” steel tubing. Welds must be complete and of good quality. Cage must be securely welded to the chassis. All roll cages must be approved by Southern Oklahoma Speedway officials.
- A minimum 3 door bars are required on the driver side. Door bars must be a minimum 1.5” x 0.083”.
- Driver seat must be mounted left side of the driveshaft loop.
- Bodies must be standard dirt late model bodies (see diagram for dimensions). Body panels must be aluminum. No carbon fiber components except for hood scoop and roof rock guard.
- Stock appearing or sloped late model nosepiece allowed. No wedge bodies allowed.
- Roof must be stock appearing and run parallel to the body. Roof may be aluminum or fiberglass. Maximum 1.5” rock guard allowed on the front of the roof. Roof may have stiffener in rear and must not exceed 1” and must be pointed down.
- Spoiler must be lexan or aluminum. See engine rules section for height requirements.
- Roof supports or sail panels must be equal length. If lexan is used in the sail panel windows it must be used on both sides (both sides open or both sides closed).
a. All racecars must have numbers that contrast to body color and must be minimum 4 inches thick and 18 inches tall for both sides and must be 4 inches thick and 20 inches tall for roof and must be clearly legible. All racecars must have numbers on the right rear corner of the back of the vehicle and must be minimum 4 inches tall.
b. Officials reserve the right to approve or disapprove any image of lettering or sponsorship on any racecar or pit vehicle entering race surface. Keep in mind this is intended to be a family fun facility.
- Must have a minimum 3 windshield bars in front of the driver and securely mounted.
- Lexan or aluminum panel in front of the driver must not be wider than the cockpit and must not extend rear of the steering wheel.
- Floor pan must be metal or aluminum and must cover the complete cockpit.
- Bottom of the seat must not be lower than the bottom of the frame rail at any point.
- Driver must be sealed off from the track, driveline, engine, fuel cell, canisters, and pumps.
- Rear view mirror devices of any kind are not allowed.
- Loose objects and/or ballasts are not allowed in the cockpit.
- Factory-manufactured high back racing seats are mandatory, and must be acceptable to officials. Homemade aluminum, plastic or fiberglass seats are not allowed. Full containment seats are recommended.
- One 12 volt battery allowed. Must be securely mounted with a non-conductive rubber or plastic covering the battery posts. Must not be mounted in the driver compartment.
- Any electronic distributor type ignition system allowed. NO crank trigger, distributorless multi-coil, or magneto ignition systems allowed. All ignition boxes or rev control boxes must be installed with the chip at easy access and clearly visible from outside the vehicle. IF YOUR VEHICLE DOES NOT ACCEPT A CHIP YOU MAY BE ASKED TO BUMP THE REV LIMIT AT FULL RPM OR TURNED DOWN TO 3000 BY TECH ONLY. ALL CHIP BOXES WILL BE CHECKED WITH A 3000 RPM CHIP.
- One 12 volt electric starter is allowed. Vehicle must leave the staging area on demand, under it’s own power, unaided, or must start at the back of the race.
- No transmitting devices of any type, unapproved cameras, or any other recording devices. Only one-way RACE-ciever is allowed.
- Any competition fuel cell (maximum 32 gallon capacity) must be mounted with minimum 2” x 0.125” straps around the cell. Cell must be contained in minimum 0.020” steel container and must be mounted within the frame and cage.
- Gasoline or methanol allowed. Only (1) 4 bbl or 2 bbl carburetor allowed. NO ADDITIVES ALLOWED! Fuel may be tested at any time by Southern Oklahoma Speedway officials.
- Mechanical fuel pumps only (pushrod cam driven or belt driven). NO electric fuel pumps.
- Fuel lines must not protrude into the driver compartment. Any manual fuel valves within reach of the driver must be isolated.
- Carburetor spacers:
a) 604 crate - may use a maximum 1” with (2) standard maximum 0.070” thick gaskets (1 on top of the spacer 1 on the bottom of the spacer.
b) 602 crate – may use a maximum 2” thick with (2) maximum 0.070 gaskets (1 on top of spacer 1 on bottom of spacer)
c) spec. motor – may use a maximum 1” with (2) standard maximum 0.070” thick gaskets (1 on top of the spacer 1 on the bottom of the spacer).
d) Open motor - may use a maximum 1” with (2) standard maximum 0.070” thick gaskets (1 on top of the spacer 1 on the bottom of the spacer).
- Steel brake rotors only, no carbon fiber, titanium, or other materials allowed.
- Rack and pinion allowed.
- No chain drive quick steers
- Steel or aluminum steering wheel quick release couplers mandatory.
- Steel or aluminum steering wheels allowed.
- Steering shafts must have a joint every 5 ft. (collapsible steering shafts highly recommended). Steel knuckles only. May be modified to suit the driver but must remain on the left side of the vehicle (no center steering).
- Must be strut or A frame configuration.
- No independent rear suspension. Steel axle or quick change axle allowed.
Shocks and Springs
- All coil springs must be steel, leaf springs may be steel or composite.
- One shock per wheel. One shock may also be used in the pull bar/lift bar area.
Tires and Wheels
- Any brand or type of wheel allowed. Must be mounted with lug nuts. No knock off or center lock wheels allowed. Maximum wheel width is 14”.
- Hoosier D55, American Racer D56 or SUPR spec 1600, or asphalt take offs allowed. Tire must durometer 55 or harder after race. Grooving and siping allowed. ABSOLUTELY NO CHEMICALS ALLOWED! Drivers found with illegal chemicals in tires will be suspended for a minimum of 4 racing nights and will lose all points year to date.
Transmission and Driveshaft
- Must have one forward, one reverse, and one neutral in working order.
- No direct drives or in and out boxes.
- Driveshafts must be painted white and labeled with the car number. Carbon fiber driveshafts are allowed. If running ballspline transmission carbon fiber driveshaft is strongly recommended.
- Crate engines – these engines are sealed at the intake manifold, cylinder head, timing cover, and oil pan with seal bolts. If these bolts are tampered with the engine will fall under spec or open motor rules. A pillar must be labeled with “Crate” if so and if found illegal for crate motor the driver will be disqualified and lose points year to date and winnings for the evening.
a) Crate or Supr Spec an weight 2150 lbs and allowed 72".12" spoiler. 8000 rpm chip supplied by driver. Must have weight decal on drivers side door post/roof.
b) Engine under 410 cubic inch must weight 2350 lbs if utilizing aluminum block or head must have 50 lbs in front of mid plate. Max spoiler 72" x 8 " with 8000 rpm chip supplied by driver.
c) Engine over 410 cubic inch will weight 2450 lbs if utilizing aluminum head or block must have 50 lbs in front of mid plate with 8000 rpm chip supplied by driver.
- No vacuum pumps.
- Cast iron or aluminum belt driven water pumps allowed. No electric water pumps. No sprinkler systems.
- Belt driven or electric radiator fans allowed.
- One radiator must be mounted in front of the engine.
- Collector type headers required. Must be a 4 into 1 design, no tri-y headers allowed. No merged headers allowed. No square tube headers allowed.
- Mufflers required. May be 3 ring, cone, or perforated inserts or pn IMCA609 muffler.
- See engine rules for details. Weight is both after the heat or qualifying races or the feature race. Any panels lost during the race cannot be added to the vehicle during weigh in.
- Any driver that finishes on lead lap and have competed in the prior two weeks competition may protest another driver that finishes in front of him or her. All protests must be submitted in writing within 15 minutes after completion of race. Once the protest has been initiated the protest cannot be recalled. All protests must be made in cash only and must be given to the appointed track official. All protesting drivers may be accompanied by one additional person. Protested drivers are allowed two additional people to aid with removing of protested parts. Teams are allowed 1 hour for removing any components except in the case a rod and piston need be removed in which 1 hour 30 minutes will be allowed. All teams are responsible for having tools necessary for disassembly. If components cannot be removed within allotted time the protested driver will be disqualified.
- Section protest – $250.00, $25.00 goes to track – Driver may protest suspension, engine, transmission, or fuel. If fuel is protested laboratory fees will be taken from protest fee. Protests may be anonymous, however, only protesting driver may be present.
- Complete protest - $425.00, $50.00 goes to track – Complete vehicle may be inspected, only one head may be removed, protesting driver chooses which side. If fuel is protested laboratory fees will be taken from protest fee. Protests may be anonymous, however, only protesting driver may be present.
- If protested driver is found legal, protest monies will be issued to protested driver less fees.
- If protested driver is found illegal, protest monies will be returned to protesting driver less fees and penalties will apply.
- Violations – First offense, Loss of points and winnings for current night. Second offense loss of points year to date and suspension up to four weeks in which decision will be made by track director.
- Any driver may protest a total of 2 times per season. A driver may only be protested by another driver a total of 2 times per season.
- SOS has the right to protest any driver at any time in which a $50.00 teardown fee will be given to protested driver if found legal.
- All decisions will be made by SOS officials and all decisions are FINAL.