Skid Plate Rules
NOTICE: ALL EQUIPMENT IS SUBJECT TO THE APPROVAL OF IRWINDALE SPEEDWAY
OFFICIALS. All CARS MUST PASS A PRE-COMPETITION INSPECTION AND ALL CARS ARE
SUBJECT TO A POST INSPECTION. NO EQUIPMENT WILL BE CONSIDERED AS HAVING BEEN
APPROVED BY REASON OF HAVING PASSED THROUGH INSPECTION.
With the exception of the following rule modifications, all cars must be 100% stock. THESE RULE WILL
BE STRICTLY ENFORCED, MODIFICATIONS NOT PERMITTED UNLESS STATED IN THE RULES.
1. Exteriors and Car Body
(a) Any 1980 or newer 4 cylinder or V-6 front wheel drive car, station wagon, or minivan, with a wheel
base of 90 inch or longer is eligible to compete.
(1) No trucks, convertibles, sub-compacts, El Caminos, SUV’s, pick-ups, Imperials, or T-tops.
(b) All cars must have complete bodies. All exterior lights, lamps, and lens must be removed.
(c) Reinforcing of frames, cross members, bumpers, or bodies not permitted.
(d) Tires and skid plates.
(1) Skid plates required on rear (rear tires must be removed). Skid plates must not be modified and
used as manufactured for Irwindale Speedway. Bent or damaged rear skid plates not permitted.
Rear axle plate alignment subject to tech inspection before race, e.g., excessive camber or
uneven plate load distribution to track.
(2) Passenger car tires only.
(3) No Light Truck “LT” or Mud and Snow (M+S) tires permitted.
(4) Wheels and tires must be OEM original size and type.
(5) Only air in tires.
(6) Tires must be DOT street legal passenger tires.
(7) No run flat tires.
(e) The height of the front and rear bumpers must be stock. Car must not be raised or lowered, and
must sit at approximate stock height.
(f) No weight may be added.
(g) Body to frame mounts must be stock. Altering body to frame mounts not permitted.
(a) All glass is to be removed from the car, except the windshield.
(1) Do not roll down windows and break them in the doors.
(b) Interiors must be vacuumed or cleaned and free from debris.
(c) All interior upholstery must be removed, except the driver's seat.
3. Engine, Cooling, Exhaust, Suspension
(a) Engine must be in stock condition and location.
(1) V-6 engines must only run on 4 cylinders, with 2 cylinders disabled. Do not allow unplugged
spark plug wires to produce an electrical arc to a ground (no sparking).
(2) Engine and transmission mounts must be stock. No welding engine mounts or adding engine
(3) Engines must be steam cleaned free of oil and grease.
(4) Engines must be stock OEM for make and model.
(b) Radiator must be in stock location. No antifreeze, water only.
(c) All suspension components must be stock.
(1) Rear suspension stock only.
(2) No reinforcing of suspension will be allowed.
(3) Making the suspension rigid or jacking up suspension will not be allowed.
(4) No truck suspension components.
(5) Automobile gasoline only. Street legal pump gasoline permitted. No additives. Gasoline shall
not be blended with alcohols, ethers, or other oxygenates and it shall not be blended with aniline
or its derivatives, nitro compounds, or other nitrogen containing compounds. Nitrous oxide
(a) Each competitor is solely responsible for the effectiveness of personal safety equipment used during
an event. IRWINDALE SPEEDAYWAY IS NOT RESPONSIBLE FOR THE EFFECTIVENESS OF
ANY PERSONAL SAFETY EQUIPMENT.
(b) Four-point roll cage required, with halo bar, 3 drivers door bars, 3 bars or “X” bars on passenger
door, cross bar behind driver and one dash crossbar. Driver’s side door plate may be used.
(1) No other interior non-OEM bars or reinforcement supports permitted.
(c) Drivers racing seat recommended.
(d) Hoods must have two pin type locks utilized in the opposite corners of the OEM hinges, or four pin
type locks in each corner. Any under-hood type latching mechanism must be disconnected or
removed. Cable wire in housing operated hood releases not permitted. Hoods must be capable of
being completely opened from the outside of car.
(e) Trunk lids must have two pin type locks utilized in the opposite corners of the OEM hinges, or four pin
type locks in each corner. Any internal latching mechanism must be disconnected or removed.
Trunk lids must be capable of being completely opened from the outside of car.
(f) All drivers must have and use a minimum 3-point seat belt system, however, 5-point recommended;
(1) OEM driver’s seat belts must be in good condition and securely mounted.
(2) Aftermarket driver’s seat belt systems should be installed in accordance with the directions
provided by the supplier and/or manufacturer.
(g) Every car must be equipped with one fully charged fire extinguisher having at least a 10B:C rating.
(1) The fire extinguisher or the fire suppression activation control must be mounted within the seated
drivers reach and readily accessible for use.
(2) Each fire extinguisher must be designed to permit visual determination of whether it is fully
(3) Each fire extinguisher shall have been rated and labeled by one of the following test labs:
(A) Underwriters Laboratories, Northbrook, Illinois.
(B) Factory Mutual Research Corporation, Norwood, Massachusetts.
(h) Every driver must wear a helmet, at least a valid Snell SA 2000 or SA 2005 Standard Snell and/or a
valid SFI 31.1, SFI 31.2 or SFI 31.1/2005, with label, at all times on the track.
(i) Every driver must wear eye protection.
(j) Approved fire suit mandatory. Gloves recommended.
(k) It is recommended the center of steering wheel be padded with 2-inch of resilient material.
(l) It is recommended padding be used on the inside of the driver’s door and on the corner post.
(m) Cars may be equipped with a battery on/off switch.
OFFICIAL 2013 SPECIFICATIONS FOR SKID PLATE CARS
Page 3 of 3
Any part of equipment found during an inspection or
any other time at any NASCAR sanctioned event
that does not meet applicable NASCAR/ Irwindale Speedway standards, must be surrendered to the
NASCAR/ Irwindale Speedway Tech Official at that time, and will not be returned. Failing to do so will
result in: a fine, and/or loss of championship points, and/or definite or indefinite suspension from
Irwindale Speedway Tech Officials reserve the right to
make final decisions in the interpretation of any
rules or race procedures at any time. No
equipment will be considered
as having been approved by
reason of having passed through inspection. Irwi
ndale Speedway Tech Officials recommend that you
carefully study the NASCAR Weekly Racing Series Rule Book in order to be familiar with all aspects of
NASCAR racing. If you are considering a part, modification or procedure not covered in these rules
contact the Irwindale Speedway Competition Director before proceeding with any purchase or
modification. If you have any questions regarding t
he rules set forth, contact the Irwindale Speedway
In keeping with NASCAR’s and Irwindale Speedway’s co
mmitment to maintaining proper balance in the
competition arena, it may be necessary for Irwindale Speedway to make rule changes and/or rule
modifications from time to time. Such changes are designed to enhance close competition. Irwindale
Speedway’s goal of a full starting field of various car makes in each race that are equally matched as
possible is certainly in the overall best interest of the sport.