Orange Show Speedway reserves the right to alter or amend the rules and regulations in the interest of safety, cost control, and/or fair competition. It is the responsibility of each competitor to read and understand the contents of these rules. If there is a disagreement or dispute regarding the meaning or application of these rules, the decision of the OSS Tech Director shall prevail.
No expressed or implied warranty of safety shall result from publications of or compliance with these rules and/or regulations. The rules and/or regulations set forth herein are designed to provide for the orderly conduct of OSS racing events and to establish minimum acceptable requirements for such events. These rules shall govern the condition of all events, and by participating in these events, all participants are deemed to have complied with these rules.
No pretense is made for having designed a foolproof set of rules and regulations. The spirit and intent of the rules is the standard by which OSS events will be governed. The OSS Tech Director is authorized to decide if an equipment change or modification is an attempt to circumvent these rules. The OSS Tech Director can and will disqualify a race car in violation of the spirit and intent of these rules. If this rulebook does not specifically state that you can alter, change, or otherwise modify something on you car, you should consider it a violation of these rules. No part is deemed to have been approved by OSS by passing through prior technical inspections.
The Tech Director shall be empowered to permit reasonable and appropriate deviation from any of the specifications herein or impose any further restrictions that in his opinion do not alter the minimum acceptable requirements. No expressed or implied warranty of safety shall result from such alteration of specifications. Any interpretation or deviation of these rules is left to the discretion of the Tech Director. His decision is final.
These rules are intended as a guide for the conduct of the sport and are in no way a guarantee against injury or death to a participant, spectator or official. All participants, guest and crew members fully understand that racing is inherently dangerous and that they are exposed to risks of death or serious bodily injury. The participants, guest and crew members voluntarily assume these risks.
BODIES- Any American 2 or 4 door hardtop car produced with a min. 108″ wheelbase. Vehicles with stock wheelbase between 101 and 107 add 100 pounds. (for ex. 1984 and up Mustangs and Camaros) No Pick-Ups, Jeeps, etc. All cars must maintain stock OEM body for year, make and model. Stock appearing fabricated steel door panels, quarter panels, and deck lids are approved. Hood and deck lid pins required. Full stock or fabricated steel floorboards and firewalls required in stock location. Rear trunk area may remain open. 5″ x 60″ rear spoiler centered on body top 3″ clear lexan. Minimum 4″ Body to the ground with driver in car after the race. Stock appearing Fiberglass or Aluminum front ends allowed. Steel or fiberglass roof ok. Any full fiberglass bodied cars are subject to 50lb penalty and loss of 1% left side weight. Dirt style bodies with open rear panels above and below rear bumper approved. Any other body combinations must be approved by tech officials before competition.
BUMPERS- Stock or fabricated bumpers are required. Front and rear bumper must be fastened to the fender and or quarter panel.
WINDOWS- A windshield made of Lexan may be used. Minimum thickness is 1/8 inch. Windshields must be supported between the dash bar and the roof halo bar with a minimum of two (2) evenly placed metal straps 1/8 inch by 1 inch or a single 1.75 inch bar in the center of the windshield welded to the dash bar and the roof halo bar. (Screen wire mesh windshield approved.) Clear Lexan rear window and B pillar window ok. Driver side window net is required on all cars. Net material must be minimum 1 inch wide and have openings of at least one (1) inch. Net must be equipped with a quick-release device on the top left corner. Mirrors ok.
FRAMES- Full NASCAR type roll cages mandatory. Bars must be a min. of 1 1/2” O.D. X .090” wall thickness, gusset as necessary for strength. Minimum of three (3) door bars required on both sides. Right side can be straight. Engine may be no further back than 1″ ahead of the Upper ball joint on the #1 Spark Plug, centered in the chassis. Fuel cell protector required, no more than the width of the frame rails. Main roll cage uprights must be fastened to floor of uni-body cars with a minimum 3/16” thick plate, top and bottom, at all four corners. Plate must be a minimum of 4” square, with (4); 3/8” grade 8 bolts at each location. Roll bar padding must be used at any point where driver may make contact. Door bars must be covered with a 1/16” thick steel metal plate, top to bottom, from front and rear uprights, welded to outside of bars. Stock frames only. No modifications allowed. Oil pans and exhaust must have a minimum of three (3) inches of clearance with the driver in the car.
HEIGHT, WEIGHT, AND WHEELBASE- Min of 4″ of ground clearance at anytime before or after the race no waiting for the shocks to release and no assistance from crew or driver wheels straight ahead. Min. Weight 3250. Max. 54% left side weight. Min Wheelbase 108″ wheelbase must remain as factory produced. Modified wheelbase (for example, factory-produced 112” Chevelle chassis that has been shortened to 108”) must add 25 lbs. No car will be shorter than 108” with the exception of factory produced 101 to 107 inch wheelbase cars (for ex 1984 and up Mustang and Camaros add 200 pounds. All lead must be securely fastened to frame using (2)-1/2” bolts or enclosed in a rail with ends secured to prevent loss or movement of weight. No lead is not to be mounted behind or on to the rear end housing, as well as, no further forward than the motor. All lead must be painted white and have car number printed on it. Any lost lead will be subject to fine of a minimum $10 per lb lost.
ENGINE- Cylinder compression limited to 200 lbs. Ford 351 C.I. Chevrolet 350 C.I. Dodge 360 C.I. Plus max .060 overbore Maximum cubic inch 360. 10.5 to 1 max compression ratio. Engine coolers allowed. Aftermarket oil pans, valve covers, water pump, fan pullies are allowed. No “stroker” or lightweight cranks allowed, factory OEM cranks only. Heads: Stock cast iron heads only. A stock head will be characterized as a cylinder head which was offered as standard equipment with no performance advantage. Vortec Head ok. No angle plug heads. No special performance options will be allowed, including but not limited to, oversize valves, special cut valves, relocated intake or exhaust bowls or ports. 1.25 inch valve springs max. No beehive or special valve springs stock type only. No porting or polishing will be allowed. Steel, Stainless Steel, or Aluminum 1.5 ratio roller rockers with stud girdle allowed. Must add 50 pounds. No Shaft rockers. Screw in studs and guide plates allowed. Engine Blocks: Stock cast iron blocks only. No modifications allowed. Stock stroke for engine being used, exp. 350 C.I. Chevy 3.48” stroke. Stock rods and pistons only after market rod bolts OK. No roller or mushroom lifters allowed. Stock type timing chain and gears only. No belts or gear drives allowed. No crank lightening or grinding allowed. No after market lightweight cranks allowed. 1” inspection hole in oil pan required. No Titanium parts allowed. Max valve head diameter Chevy 1.94 intake 1.50 exhaust Ford 1.78 intake 1.45 exhaust Dodge 1.88 intake 1.60 exhaust U. Roller tip steel rockers allowed, any ratio. Any hydraulic cam and hydraulic lifters. Crate 602 legal, no certification required.
CARBURETOR- Holley #4412 or Holley Keith Dorton #80583 Box stock except for the following: Gasket, bowls seal, accelerator pump squirter, power valve, jets, sight plug, choke plate, shaft and choke horn may be removed straight cut. 2 carburetor return springs required must be mounted to engine block. Maximum carburetor adapter height including gaskets is 1.25 inches. Any mass produced aftermarket Aluminum dual plane intake manifold permitted. Edelbrock Torker 2 and Edelbrock Performer p/n 2101 and 2104 are also permitted.
AIR CLEANERS AND FILTERS- K&N air filters are allowed.
ENGINE MOUNTS- All mounts must be securely bolted and adjustable mounts are not permitted.
ELECTRICAL SYSTEM- Stock type ignition only. No performance after market distributors, components, or magnetos allowed. No msd, or dui components allowed. All cars must be equipped with a master electrical switch located in the cockpit of the car. The switch must be within reach of the driver and safety crew from the left side of the car. Switch must shut off car. Batteries must be securely mounted within the confines of the body and behind the driver, in front of the rear axle and contained in electrically insulated container. No marine or plastic type boxes allowed.
ENGINE COOLING SYSTEM- Stock or electric fans are permitted. Water overflow catch can unit required. One (1) quart minimum, vented out to windshield, metal or plastic, mounted in engine compartment. No anti-freeze or similar products. This is a finable offense. Water Wetter ok.
ENGINE EXHAUST SYSTEMS- Any Stock cast exhaust manifold. Headers are approved Headman Hedders P/N 68600 is recommended. Any steel equivalent street type header with standard 3″ max collector. No Modifications. No Header wrap. An approved muffler is mandatory, must not exceed 95 db @100 feet. Exhaust must extend past driver’s compartment and remain under car. Exhaust may exit on passenger side of race car in front of right rear tire and must have 4 inch ground clearance. 3″ max exhaust pipes, 2 into 1 collector, 5″ max past 2 into1. Must have 1” inspection hole inline with #3 rod.
DRIVE TRAIN- Clutch will be stock OEM steel type only. Aftermarket master and slave cylinder allowed. No lightweight or racing type disc, pressures plated, or flywheels allowed. Scatter shields mandatory! Steel Locked, limited slip, or positive-traction differentials are permitted. Rear end must be centered in car. Steel Floater type rear ends are permitted. No hollow axles. Stock Automatic transmissions optional, Min 10″ torque converter must be operational. Must have all gears. Transmission oil cooler required. Any OEM Steel rear end allowed. Must be mounted exactly as old rear end that was removed, may be used in any MFR line. 2 driveline straps, 1” x 1/8” required, mounting to be within 6” of the U-Joints are required on rear drive vehicles. Steel Drive shaft must be painted white and have car number on it for on track visibility in the event it should become separated from the car. 3 or 4 speed stock OEM transmission with all gears no modifications. No cambered or toe rear ends.
SUSPENSION AND BRAKES- Stock OEM type lower control arms only equal length, no modifications allowed. Upper tubular A-arms allowed. Must be steel one piece, either steel or aluminum cross shaft allowed. No bearings or heim joints. Stock OEM upper A-arms allowed. Any OEM factory production type of balljoint may be used. No “Mono Ball” balljoints. Stock Steel unmodified Spindles from same manufacturer. No heim joints. Stock upper control arm mounting may be moved for caster/camber. After market or fabricated upper control arm mounts are approved, cars running these style mounts may continue to do so, however, the mounting location of these perches must coincide with stock pick up point measurements ( example- camaro measurements 3 ½” front and 2 ¼” rear on both sides). No heims, no sliders boxes, no adjustable upper a arms. One mounting plate per side must contain both front and rear mounting hole. Adjustable with shims between mounting plate and upper a-arm only. Racing springs ok. Non- adjustable Racing shocks ok. No Schrader valves. No external reservoir. Lowering blocks allowed. ( leaf spring sliders approved.) All other suspension components must be of original design and origin for the chassis used. No after market look alike parts to widen suspension. Maximum overall width (front or rear) shall not exceed 67” from inside of wheel to outside of wheel at 4” ride height. Front tire width will be measured at spindle height. NO EXCEPTIONS! No aluminum shocks permitted. No weight jacks. Adjustable spring spacers allowed. Cars with weight jacks or moved shocks will carry 50 pound weight penalty. After market pedal and master cylinder assemblies allowed. Rear disc brakes allowed. All components must be steel. No light weight parts. Stock, 4 wheel hydraulic brakes required, and all must be in good working order. One adjustable brake bias valve allowed. Any steel 1 piece sway bar mounted in the stock position. NO bump stops or travel limiting devices of any kind allowed.
STEERING COMPONENTS- Stock type steel steering components only. Adjustable steel tie rod ends and sleeves approved no heim joints. Quick release steering wheels are required. Steering column must be collapsible. U joints are acceptable.
FUEL SYSTEM- Pump Fuel only. No Additives. No octane boost. (No EC-85 Fuel, No Alcohol) All cars must be equipped with an approved fuel cell, securely mounted in the trunk area. Minimum 10” ground clearance. Fuel cell must be mounted with steel framework (1 inch x 1 inch, .065 inch minimum) and must have a vent hose and the hose must have a check valve in the end. Fuel cell must be totally enclosed in an 18 gauge steel box with a ½ inch drain hole in the lower right rear corner. Ground strap required from fill neck to frame. Maximum fuel capacity 22 gallons. No electric fuel pumps permitted. Fuel lines may not enter driver’s compartment.
TIRES AND WHEELS- Steel wheels are mandatory, maximum 8” width any offset. Tire and wheel must stay inside of fender and quarter panel. 5/8” wheel studs required on all four (4) wheels. No Bleeders. Wheel spacers allowed. American Racer 970 treaded tire only. No soaking or treating or modifying (cutting, grinding, camber cutting, etc.). 6 tires may be purchased on opening night, with 2 tires available at each race thereafter. Cars failing to make opening night will be able to purchase 4 tires at their first race.
Seats and Safety Equipment- For all safety equipment. It will be the sole responsibility of the driver, not OSS, their agents/officials or corporate officers to ensure that his/her safety equipment is correctly installed, maintained, and properly used. Please refer to manufacturer installation and usage guide lines and adhere to them. Aluminum professionally built high back racing seat required. No plastic, etc. Padded headrest required. Seat must be securely bolted to a mount assembly that is an integral part of the roll cage. 6 bolts min no smaller than 3/8” diameter bolts. A five (5) point safety harness, with quick release is mandatory! 3” wide lap belt, 2” or 3” shoulder belts, and a 2” submarine belt. All belts shall be attached to roll cage using minimum 3/8 grade 8 hardware and safety cables. Loop around belts ok. Cotton harness components prohibited. Safety harnesses/seat belts may be no more than three (3) years old. Must have manufacture date. Snell SA2010 or SA2015 helmet required. Full face helmets with Lexan face shield recommended. Nomex helmet, skirt, and Nomex covered chinstrap highly recommended. A HANS or Hutchens type head and neck restraint device is strongly recommended; minimum of a neck roll required. Window net mandatory! Minimum 1” webbing with release at top only. It is required that all window net releases be updated to the quick release seat belt type with releases located and facing the outside of the car. No close mesh off-road type allowed. Fire suit mandatory at all times 2-layer one piece suit recommended. Two piece suit ok. Single layer proban suit ok with the use of nomex underwear. Approved racing gloves mandatory. No welding gloves, gardening gloves, etc. Approved racing shoes mandatory. Eye protection is mandatory and must be in proper place at all times. Current test date (2 pound minimum) fire extinguisher to be installed in the car within drivers reach while strapped in. Steel mounts only, no plastic. All cars will be required to have in their pits a minimum of one five pound, Halon or dry chemical fire extinguisher. This is to be visible to tech officials and all crewmembers. All crew members must be made aware of this location, and knowledgeable in the use of the fire extinguisher. Car and driver will be required to make safety rule violations comply PRIOR to racing any event. The use of a two-way radio with a spotter and/or pit crew is mandatory. OSS official radio frequency is 462.6750. It is highly MANDATORY that all racers monitor this frequency during all races. This will speed up getting cars lined up during yellow flags.
APPEARANCE AND IDENTIFICATION- All cars are to be neatly and brightly painted. Numbers will be a minimum of 18” on the roof and both door panels. Numbers on the roof to face toward scoring tower (flag stand). No aluminum foil type lettering. Numbers assigned to car will be displayed on the top right front of windshield, 3” minimum. Drivers first and last name to be placed above each door, on the roof in 3” letters minimum. No duplication of numbers, additional letters such as “X”, “Y”, “and N” are not to be used. Advertising or names on the windshield is not permitted. This will be reserved for a series sponsor. Advertising that is deemed to be unsuitable/offensive, will not be allowed. Decision of OSS Tech Director will be official. Series sponsor decals, if any, must be placed on designated location of car to be eligible for awards. This is to be completed PRIOR to competing in any event.
CHEVROLET CARS PRODUCED WITH 116″ WHEELBASE AND LONGER A. 400 cubic inch small block with 4BBL Carburetor approved. This combination must weigh minimum 3350lbs 54% left side weight after the race and cannot have interior metal, trunk, hood, roof, or deck lid gutted. Please call tech director if you plan on running this combination. Must comply with all other class rules. Any gutted factory produced Full Frame car min 112″ wheelbase and longer must weigh minimum 3200 lbs. 54% left side weight after the race. Please call tech director if you plan on running this combination. Must comply with all other class rules. Stock car usa with 400 ci motor must add 50 lbs.
Technical Director Billy McCray (951)-250-7683 or Chad Agre (909)-855-9835
All rules are subject to change at any time if deemed necessary to ensure even competition within the division.
