DIRT MotorSports Standardizing Street Stock Rule Book Across NationWeedsport, NY – Jan. 24, 2022 – By Cory Reed, DIRT NorthEast Competition DIRT MotorSports has developed a national sanctioning group called DIRTCar with the goal of standardizing rules and building regional and national point structures. It is the goal of DIRT MotorSports to convert the Street Stock/Pure Stock class that has run over the years to UMP DIRTCar Street Stock, sharing common rules nationwide. UMP officials stated at the beginning of the 2006 season that they would implement 4 to 5 rules for the 2022 season with more to follow over five years. Some of those UMP rules have been implemented in the 2022 NE rulebook. The rules to follow parallel most of what UMP DIRTCar allows. Two exceptions include: 1) UMP DIRTCar Street Stock allows any cast iron cylinder head and 2) An open aluminum intake; both of which are NOT included as options in 2022. However, it is the intention to be governed exclusively by the UMP DIRTCar rulebook within the next two years. An announcement will be made late in the 2022 season regarding cylinder heads and intakes. Car Eligibility1. American or Canadian made only 1968 to current. 2. All cars must be sedan type. 3. No front wheel drive, compact, sports, foreign cars, trucks or convertibles! 4. No independent rear suspensions. 5. Weight - 3200 lbs. minimum at all times without adding fuel. 6. O.E.M. defined as Original Equipment Manufacturer. 7. No Strut or Torque Arm cars allowed. 8. No Camaro, Firebird, IROC, Trans-Am, or Mustang cars 1982 to present. 9. Either perimeter or offset chassis allowed. Inspection: All cars are subject to inspection at any time during the season to ensure compliance with these rules. Especially following major damage from wrecks.
Tech Inspectors & Track Officials: Reserve the right to perform and in depth technical inspection on any car they feel is not in compliance with these rules no matter what position the car finished in the event. Any car found to be in violation at a pre-race inspection, must make it right before it can race! Disqualification: Any car found not in compliance with these rules MAY be allowed to participate in that weeks event, (with the officials consent) but will automatically be disqualified from receiving prize money and points for that event, and will not be eligible to participate in future events until the infractions are corrected. RULE INFRACTIONS CONCERNING THE PERSONAL SAFTEY OF ANY AND ALL WILL HAVE TO COMPLY BEFORE ALLOWED TO RACE! Any car after post race inspection found illegal, will be subject to disqualification, not receiving prize money and points for the nights event! Frames1. A-frames, engines, and all parts must remain in stock O.E.M. location. 2. Uni-bodies can be connected with 2 x 3 MINIMUM. 3. Rear hump to back of car may be 2 x 3 and must conform to stock O.E.M. specifications. 4. No tubing or bracing under main frame rails. 5. Wheel base 98" minimum. Wheelbase must be stock to frame being used year make and model. By 2010, the wheelbase must be 108” minimum. Engine Specifications 1. All engine parts must remain in stock OEM, including all blocks and internal parts. No aluminum blocks.2. Engines may be bored .060 MAXIMUM, 400 cubic inch MAXIMUM. A 400 may be bored .030 with .007 for wear. Max overbore: GM and FORD ..060" Chrysler .030.3. Cylinder heads: SPECIAL NOTE-Only cylinder heads produced by Chevy, Chrysler, or Ford prior to 1996 with their part and casting numbers approved by DIRT and pass the ball check will be eligible to run. Chevy Vortex and Ford GT NOT ALLLOWED. Cast Iron OEM stock production only. Heads must be manufactured by manufacturer of engine block. Sand blasting, bead blasting, acid dipping, porting, polishing, and welding are prohibited. No relieving or enshrouding of valves in combustion chamber. Any angle valve job will be permitted as long as it is done on a machine that concentric to the valve guide center. Any amount of valve seats per cylinder head will be allowed to be installed for the purpose of repairing a head. No hand grinding, sanding, blending, or de-burring where a cutter or stone leaves off. The amount of metal you will be able to remove in the bowl areas on both intake and exhaust will be governed by the same method used by all DIRT inspectors at all DIRT tracks. Method of checking will be as follows: on the exhaust side, the header will have to be removed and then the inspector will place a tool in the port which will consist of a .531” diameter ball bearing welded to a flexible shaft. With the valve fully opened, the ball will be place against the valve stem and moved to a full circle around the valve stem. If the ball drops down through the valve seat in any position around the full circle of the valve stem, it will be deemed illegal. On the intake side, the carburetor will have to be removed and in some cases, the intake manifold for the same type of procedure, only the ball size will be .787”.. NOTE: These methods of checking the head will hold true with a cold or hot engine. Any carbon fiber parts used in these engines WILL BE ILLEGAL. Valve stem maximum and minimum diameter plus or minus .005” must be: Chevy 11/32”-Ford 11/32”-Chrysler 3/8”. Milling or angle milling of the cylinder head to any amount will be allowed. No epoxy or coating of heads allowed. NOTE: Anyone found to be illegal in any way in the cylinder head, carburetor, or distributor area will result in complete DQ, losing all monies and points for the night. No protest or appeals will be given on cylinder head, carburetor, or distributor infraction.4. Carburetor: Normally aspirated engines only. Stock OEM Holley carburetor, part #4412 is ALLOWED and must run a maximum spacer adapter of 1 1/16", including gaskets. Maximum throttle bore 1-11/16" and maximum Venturi bore of 1 1/4". No speed parts. No race type carburetors. No boring or polishing of throttle or Venturi bores allowed! No modifications of any kind will be allowed to these carburetors except those listed below (box stock only). Conventional round type air cleaners only. Air cleaners that provide ventilation through the top cover (such as the K&N brand) are permitted No air induction plastic carburetor inserts or other devices to direct air into intake. No air diffusers are allowed. CARBURETOR MODIFICATIONS ALLOWED ARE LISTED BELOW, ANY OTHER MODIFICATION NOT MENTIONED IS NOT LEGAL.a. Holes drilled in the throttle plates for proper idling. b. Drilling, tapping, and plugging of unused vacuum ports. c. Welding of throttle shaft to linkage arm. d. Drilling of idle of high air correction jets. e. Milling of center carburetor body metering block surface a maximum of .015" on each side. f. Removal of choke plate and shaft. g. The jets may be changed as needed. Any other changes to carburetors, such as drilling, smoothing, matching, or milling is NOT ALLOWED. Stock OEM only. 5. Throttle Linkage: May be of the solid rod type. No throttle cables are allowed for any event! Dual throttle springs are mandatory 6. Intake Manifold: Stock cast iron OEM manifold. Only. 7. Pistons: Flat top O.E.M. pistons allowed. 2 or 4 valve relief only, No pop-up's allowed. Forged piston optional. 8. Rods: Steel I-beam rod allowed- stock length, no machining, polishing, or deburring allowed. 9. Camshaft: Any hydraulic or solid type cam only. Any make. No roller cams or lifters allowed. 10. Rocker Arms/Rocker Studs: Rocker arm studs may be pinned. Screw-in studs will be allowed. Steel-tipped Roller rocker arms are allowed. No steel full roller rocker arms allowed. 11. Crank: Stock O.E.M. only. No modifications EXCEPT for balancing. No lightning or boring allowed! Minimum crank weight of 46 pounds. 12. Aluminum pulleys allowed. 13. NO COATINGS ON ANY ENGINE PARTS! 14. Exhaust Manifold: No center dump exhausts. Stock O.E.M. exhaust manifolds only. Passenger-type only, no 2 into 1 exhausts. No grinding, polishing, porting, or acid dipping. 15. Headers are allowed, 1 5/8" tube only. Step or merged collectors are NOT allowed. 180º Headers are NOT allowed, but crossover headers are allowed. Fully welded exhaust highly recommended. 16. MUFFLERS AND EXHAUST SYSTEM MANDATORY: Only Stock or “California Turbo” mufflers will be allowed. Mufflers may not be altered or modified from original design in any way. Maximum exhaust pipe diameter will be 2 ½”. Complete exhaust system must remain under car and exit to rear behind driver. 17. Ignition: Stock O.E.M. ignition system only: Stock OEM breaker point or HEI (Electronic Ignition) distributors with OEM coils. No after market parts allowed! No MSD boxes or MSD distributors! 18. Fuel Pumps: Must be stock OEM metal type or after market replacements. No glass bowls, No high volume pumps requiring a pressure regulator! Fittings are available to adapt steel braided fuel hose to them from several sources.
Chassis and Suspension 1. Fuel Cell: Max. 22 gallon Capacity cell will be centered in trunk and if trunk floor is removed will not extend below the frame rails behind the rear axle. The fuel cell will be secured with a minimum of two 1" x 1/8" flat steel straps secured by 3/8" bolts. Fuel lines will be made of steel tubing or steel braided hose from fuel cell to carburetor through the center of driver's area with a fuel shut off valve painted a bright color (red, yellow, orange, or white) located next to the driver's seat. OEM rubber fuel hose and OEM fuel tanks are not allowed! A one-way check valve MUST be installed in the vent line to prevent spillage in the event of a roll over. 2. Fuel: Pump fuel or SUNOCO racing gas ONLY! No additives or boosters permitted. This will be strictly enforced! 3. Radiator: Aluminum radiators are allowed. Must remain in stock location. Radiator catch can mounted in the engine compartment only! Mandatory. 4. Transmissions: All transmissions are to remain stock OEM with all gears operational. Scatter shields for manual transmissions are mandatory. Flywheel and clutch assemblies will be stock OEM. No triple disc or after market parts allowed! Stock OEM pressure plate. Automatic transmissions must run stock OEM Torque Converter and a shatter blanket is highly recommended! No mini converters. No hollow converters allowed. No lock up converters No ball valve type hydraulic transmission allowed! All cars must have reverse gear in working order. No parts added, removed or altered. 5. All parts on suspension must be completely stock O.E.M. parts. Only changes allowed are changes that rules state otherwise. All suspensions parts must be of same make and model as original car. 6. Coil and Leaf springs may be OEM or after market. Springs must be magnetic steel only (no carbon fiber). Rear springs must match chassis being used. GM for GM, FORD for FORD, CHRYSLER for CHRYSLER. Aftermarket springs with spring cups allowed. Non-adjustable. No Mono leaf allowed. 7. One (1) shock per wheel only. 8. Shocks may be remounted. After market WB shocks allowed. Non-adjustable. Non rebuildable. 9. Shocks. Steel bodied after market shocks with welded ends are allowed. Non-rebuildable. Non-Adjustable. Gas filled OEM replacement will be allowed. A $90.00 maximum racer net price must be maintained! 10. Driveshaft: Steel driveshaft only. Steel drive flanges on rear and transmission only. All cars must have a suitable driveshaft sling behind transmission, under front U-Joint, to prevent driveshaft from digging into track or bouncing out or up into car in case of failure. Driveshaft loop made of at least 1/8" thick x 2" wide material. Installed no more than 6" behind the front of U joint. DRIVESHAFT MUST BE PAINTED WHITE FOR SAFETY. 11. Rear End: Rears must be stock for model running. Mini-spool or welded spiders allowed. 9" FORD rear end highly recommended. 12. Brakes: After-market pedal assembly will be allowed with balance adjuster. Calipers must be OEM or replacement parts that meet OEM specifications. All components will function as designed and vehicle's brakes are subject to inspection at any time for proper operation. Absolutely no aluminum calipers or light weight drums or rotors (drilled) will be allowed. Four wheel disc brakes will be allowed. No shut-offs allowed. 13. Battery: Must remain in the engine compartment sealed from driver's compartment and be securely fastened to prevent contact with metal parts and damage in the event of a roll over or impacts. Battery must under the hood only. A Battery Disconnect on the Hot Side in reach of the driver and officials is MANDATORY! 14. Charging System: Must be maintained in a functional state to allow car to be self-starting. Any car that will not start on its own will be placed at the rear of the field no matter where handicappers place car in field. 15. Tow Hooks: Or easily accessible lifting cables front and rear are mandatory. Car will not be allowed on the track without them. BodiesOption A: Stock OEM Body1. Bodies must be sedan type only.2. Bodies and overall appearance must retain all stock O.E.M. dimensions.3. No lowering or offsetting body. Body must be centered on chassis. 4. All doors must be welded or bolted closed. 5. Interior must be gutted. 6. All body moldings and door handles must be removed. 7. Inner fenders may be removed. 8. All cars must have a rear firewall, between the driver and the fuel tank completely closed off. 9. Floor must run from door to door and front to rear. 10. Firewall between the driver and engine must be completely sealed off. 11. Driver must be located in stock O.E.M. position. 12. ALL BODY PARTS, STOCK O.E.M. ONLY. 13. No holes in the hood or any type of hood scoop. 14. Exhaust system must exit behind the driver. 15. No rear spoilers. 16. No cockpit style tinwork. Option B: Aftermarket Body1. General Appearance: Aftermarket Bodies are allowed, providing they look stock and match the wheelbase of the frame being used. Bodies must be stock appearing and mounted in stock location on frame. Stock manufacturers sheet metal or aftermarket body must maintain the OEM fit and appearance. No air dams, skirts or other aerodynamic enhancing equipment are allowed on the car, front or rear. Bodies, engines and chassis must match GM for GM, Ford for Ford and Chrysler for Chrysler. No Wedge shaped bodies or flat body panels are allowed. Officials reserve the right to reject and body or parts. 2. Body Width: Maximum body width measured anywhere along the contour of the car may not exceed 82". 3. Allowable Body Materials: All parts of the body must be either steel or aluminum, except the hood, roof, front and rear roof supports which may be aftermarket approved fiberglass. 4. Roof: Must be stock OEM steel or approved one-piece fiberglass construction. Must also maintain stock contour and appearance. 5. Hood/Trunk: One-piece steel, aluminum or fiberglass. Only hood scoop to be allowed will be fiberglass hood with 2 1/2" maximum hood scoop. No steel or aluminum hoods with add on hood scoops will be allowed! No holes may be cut into hood for any reason. Lift off hoods and trunks are allowed as long as they are fastened safely to properly seal off engine and trunk area. All hoods with scoops must be sealed at back of hood scoop to protect driver. 6. Bumpers/Nose: Front and rear bumpers may be of the hard plastic type. Front nose must be stock appearing. No dirt style noses will be allowed such as Performance part numbers 331040, 281040, 251040 etc. Front and rear covers may not be widened from stock width. Tailpiece must be stock with a bumper cover. No flat sheet metal will be allowed. 7. Dash: Dash may be removed, providing the steering column is secured and remains in stock location. New dash may not protrude any further back than original OEM dash, and must be even (in one plane) all the way across the car. 8. Firewall: A full steel firewall of at least 18-gauge thickness is mandatory with all holes securely covered to isolate driver from fire front and rear. Front and rear firewall must extend from fender to fender in as straight of a line as possible. No excessive firewall cutouts or tunneling for exhaust clearance allowed. 9. Inner Tin Work: No sheet metal extending from passenger side dash back to rear shelf is permitted. No cockpit type tinwork allowed! 10. Floorboard: A full floorboard must be retained from the engine firewall to rear firewall and from door to door. Passenger side floorboard may be level from top of transmission and drive shaft tunnel but no higher, to allow ground clearance of both exhaust pipes and mufflers. No angular tinwork or cockpit ting allowed. 11. Spoiler: No spoilers allowed of any type. 12. Visors: One 3" visor allowed, from a pillar to a pillar, and from top of windshield seam down. 13. Rub rails: External rub rails are optional. The only allowable rail is a single 1” wide x 2’’ high steel tube mounted flush to the body panels between the wheel openings. The tube must be cut at a 45 degree angle and capped with no sharp edges. Rails must be securely anchored. Wheels and Tires1. RACING WHEELS ARE MANDATORY! All wheels will be steel (no aluminum) Minimum width 7", maximum width 8". 2. A maximum offset of 2" will be allowed. All wheels will be measured from the outer bead radius to center of bolt flange. No tolerance allowed 3. No wheel plugs or covers. 4. 1/2 -inch wheel studs MANDATORY and will be STRICTLY enforced. 5. 1" lug nuts are mandatory on all 4 wheels. 6. Tires will be street tread only with a maximum of 8" tread width, (no snow, mud, studded, light truck, or directional tires!) Radial tires are highly recommended. Allowed Options: Street D.O.T. Tire, Diameter 70 Series Tire or American Racer Tire #2656015. OPTIONAL: HOOSIER TIRES PART #36103500 & #310605500 & #36860- soft/medium. MAY BE USED. Track will dictate which Hoosier tire compounds that will be allowed. Must run Hoosier Tires to be eligible for UMP DIRTCar regional or national point funds. Bumpers1. All bumpers must be stock O.E.M. 2. Bumpers may be reinforced behind the bumper cover only. 3. On side rail on each side of the car between the front and rear tire. Maximum of 1x2 inch O.D. will be allowed. No sharp ends. Ends must be capped off.
Roll Cage1. A mandatory 6 point roll cage must be used to surround the driver and must be constructed of 1 1/2" or 1 3/4" outside diameter steel tubing with a 1/8" wall thickness. Welding of joints must be continuous around the entire joint, no partial beads or spot welding. Welding will be of good quality, excessive slag and overheating of steel (burn through) will be cause for rejection. The uprights must be mounted on the left and right sides of the frame with one upright in front and one behind driver on each side of frame. They must be securely welded to the flat horizontal portion of the frame not the kick ups. The four bars joining the uprights must be at least 2" above the helmet height of the driver when strapped in the car. There will be at least 3 horizontal bars on both sides of the car connecting the main uprights; these horizontal bars must have at least one set of vertical supports centered between the main uprights to tie the bars together. A diagonal bar from the top left bar down to the top horizontal bar in the driver's door is highly recommended. A horizontal bar at dash height must connect the front uprights. The rear uprights must be connected from the top of the left rear upright down to the bottom of the right rear upright. Any joint between two or more bars must be gusseted with at least 1/8" steel material for added strength. Flush grinding of welds is not permitted. Threaded pipe, angle iron, pipe fittings, lap weld pipe, soft metals such as aluminum, and channel iron will not be used. Any bars running through the engine and trunk compartments will be completely within the body panels of the car. A front hoop to protect the radiator may be used but will be at least 4" behind front body parts to prevent it from being used as a push bar. Two (2) additional horizontal bars behind the fuel cell to provide crush protection are highly recommended: One(1) bar in this location is mandatory.
Safety1. All glass must be removed. 2. No mirrors. 3. Window net on driver's side mandatory. 4. Mandatory for the driver to wear a neck collar. 5. A full screen must replace the windshield. 6. Racing seat belts with shoulder straps mandatory. 7. Steel braided fuel line optional. 8. FUEL CELL MANDATORY. Fuel cell in trunk only, securely mounted. Must open truck to refuel. 22 gallon tank maximum. Fuel lines through driver's compartment must be in steel pipe or conduit. 9. Weight must be lead weight or steel plates mounted to frame by Weight Ballast Clamps. No welding weight to frame allowed. No Dumb Bells, etc. to be used. All weights being used must be painted white and have car number on it. No tolerance at all on this rule. If it is not up to specifications, car will not be allowed to race until it complies. 10. All cars must have the hood on while on the racing surface. 11. All drivers must have a full-face approved helmet and gloves. Driver must also have a fire suit (no overalls). Fire resistant underwear, arm restraints, and racing shoes highly recommended. 12. One Way Radio/Scanner is MANDATORY. Frequency is 454.000. 13. Aluminum Racing Seat: High back are mandatory. No fiberglass seats. Seats must be securely fastened with 6 bolts, 4 on bottom and two on the back, to the frame/ or roll cage only! 14. Helmets: All drivers must wear a 2000 or newer Snell approved helmet (full face is highly recommended) no more than 5 years old (date of manufacture tag must be present inside helmet) and a fire suit, one piece is highly recommended. Fire retardant underwear, gloves, and racing shoes are highly recommended. 15. Seat Belts and Harness: All cars must be equipped with a 5-point seat belts to SFI 16.1 specifications. Belts older than 36 months (from the date of manufacture) will not be permitted. All belts must be securely fastened to the frame or cage. Bolts may not be inserted through the webbing for mounting. Seat belt webbing that comes into contact with any sharp or and metal edge must be protected from that edge by means of push on grip vinyl trim. The areas of concern are the webbing slots in the metal racing seats. All the seat manufacturers either roll the edge or supply the seat with trim protecting the webbing from abrasion or cutting under impact conditions. Webbing entry slots into the seat with an existing metal roll of 1/8" smooth radius will not require vinyl trim. 16. Fire Extinguishers: Capable of putting out fuel and oil fires must be on hand in the cars pit area are MANDATORY! It is recommended that you have one in the car! The extinguisher will be of the class B, C, or B/C type only. No air pressurized, refillable, water Class A type extinguishers will be acceptable for the purpose of extinguishing fires in the pit area.
Protests: See the DIRT rulebook. Procedures: All on and off track procedural rules, see the DIRT rulebook.
The DIRT MotorSports™ Advance Auto Parts Modified Series is brought to fans across the Northeast by several sponsors and partners, including series sponsors Advance Auto Parts, Hoosier Racing Tire and Sunoco Race Fuels. Promotional partners include AMB i.t., F.X. Caprara Car Companies and the University of Northwestern Ohio and the contingency sponsors are Bert Transmission, Bicknell Racing Products, Bilstein Shocks, Brodix Cylinder Heads, DART Machinery, Holley HP Carburetors, MSD Ignitions, Miller Electric Manufacturing Company and Wrisco Industries. |