THOMPSON INTERNATIONAL SPEEDWAY

2004

MINI STOCK RULES

BODY:

GENERAL: ALL PARTS IN A MINI STOCK MUST REMAIN STOCK OEM UNLESS NOTED IN THE RULES. ANY MAKE, 1978 OR NEWER, FRONT OR REAR WHEEL DRIVE, 4 CYLINDER, 2 DOOR COUPE CAR WITH A MAXIMUM WHEELBASE OF 105” ALLOWED. NO STATION WAGONS, SPORTS CARS OR CONVERTIBLES. NO MID OR REAR ENGINES. NO 4 WHEEL DRIVES.

ALL BODY PANELS MUST REMAIN STOCK, INCLUDING ANGLES AND OPENINGS. DOOR PANELS MAY BE REPLACED WITH SHEET METAL PROVIDED THAT IT FOLLOWS THE  SAME CONTOUR AS THE ORIGINAL BODY PANEL (MUST BE STOCK APPEARING). THE HEADLIGHT AND TAIL LIGHT OPENINGS MUST BE COVERED WITH SHEET METAL. NO HOLES IN THE REAR BUMPER OR TAIL PANEL. THE ONLY PANELS ALLOWED TO BE GUTTED WILL BE THE HOOD, ROOF, TRUNK LID AND THE DOORS. DOORPOST AND INNER QUARTER PANELS MUST REMAIN. FULL STOCK FLOOR PAN AND STOCK FIREWALL MUST REMAIN. THE TRUNK FLOOR MAY BE CUT FOR THE INSTALLATION OF THE FUEL CELL ONLY. FWD CARS MAY REMOVE THE INNER SHEET METAL PANEL IN FRONT OF THE STRUT TOWER TO THE RADIATOR SUPPORT.

BUMPERS; STOCK BUMPERS ONLY. FACTORY ABSORBERS MUST BE REPLACED WITH STEEL BRACKETS. THE OUTSIDE EDGES OF THE BUMPER MUST BE CAPPED TO PREVENT HOOKING. AFTERMARKET FRONT AND REAR COVERS ALLOWED FOR MODEL BEING USED. NO “DIRT” OR “OUTLAW” TYPE  BUMPER COVERS.

MAXIMUM REAR SPOILER; 3” HEIGHT.

GLASS: FULL WINDSHIELD REQUIRED. QUARTER GLASS ALLOWED.

BODY SPOILER: SIDE SKIRTS ALLOWED BETWEEN WHEEL OPENINGS. MUST FOLLOW CONTOUR OF BODY AND MAY NOT BE STEPPED OR ANGLED. SIDE SKIRTS MUST MAKE RIDE HEIGHT.

INTERIOR SHEETMETAL: DASH MAY BE REMOVED AND REPLACED WITH A FABRICATED DASH. FRONT FIREWALL MUST BE STOCK. ALL HOLES IN THE FRONT FIREWALL MUST BE COVERED WITH SHEETMETAL. REAR FIREWALL MAY BE FABRICATED, BUT MUST FOLLOW STOCK CONFIGURATION. HATCHBACK CARS MUST FABRICATE A REAR FIREWALL TO PROTECT THE DRIVER FROM THE FUEL CELL. FIREWALLS MUST BE WELDED, NOT RIVITED. NO ENCLOSURES AROUND DRIVER. ALL INTERIOR SHEETMETAL MUST BE MINIMUM .031” STEEL. DRIVER’S SEAT CANNOT BE FURTHER BACK THAN THE TRAILING EDGE OF THE DOOR.

FRAME/CHASSIS;

ALL CHASSIS PARTS MUST REMAIN STOCK, UNALTERED, WITH THE FOLLOWING EXCEPTIONS; THE RIGHT LOWER A-FRAME MAY BE LENGTHENED TO OBTAIN PROPER CAMBER ANGLE OR THE RIGHT STRUT TOWER MAY BE CUT AND MOVED A MAXIMUM OF 1” FROM PASSENGER SIDE TO THE DRIVER’S SIDE ONLY (NO MOVING FRONT TO BACK). NO OTHER MODIFICATIONS TO THE STRUT TOWER ALLOWED. STRUT TOWER MUST BE COMPLETELY RE-WELDED. STRUT SUPPORT BRACKETS, FABRICATED OR AFTERMARKET MAY BE USED ON FRONT AND REAR SHOCK TOWERS. SHOCK TOWER LOCATIONS MUST REMAIN STOCK. AFTERMARKET OR FABRICATED ENGINE CRADLE SUPPORTS MAY BE ADDED TO STIFFEN SUSPENSION. FRAME REPAIRS IN FRONT OF THE FRONT STRUT/SHOCK TOWER AND BEHIND THE REAR STRUT/SHOCK TOWER MAY BE FABRICATED WITH 2” X 3” X .083” MAGNETIC STEEL TUBING. REPAIRS MUST FOLLOW THE STOCK CONFIGURATION OF THE STOCK CHASSIS.

FUEL CELL HEIGHT: MINIMUM 6”

BALLAST WEIGHT: ADDED WEIGHT MAY BE MOUNTED UNDER CAR SECURELY BOLTED TO THE FLOOR PAN AND UP AS HIGH AS POSSIBLE. THE WEIGHT MAY NOT BLOCK AREA BEHIND THE LEFT FRONT TIRE AND THE AREA IN FRONT OF THE LEFT REAR TIRE, IN ORDER TO CHECK CHASSIS (FRAME) HEIGHT. THE LOCATION AND MOUNTING OF WEIGHT IS PER TECHMAN’S APPROVAL. BALLAST WEIGHT WILL NOT BE CHECKED FOR RIDE HEIGHT.

GROUND CLEARENCE: 5 ½”

CAR WEIGHT: CARS WITH ENGINE DISPLACEMET UP TO 1999 CC’S, MINIMUM WEIGHT IS 2100 LBS.. CARS WITH ENGINE DISPLACEMENT OF 2000 CC’S AND GREATER, MINIMUM WEIGHT IS 2400 LBS.. CHRYSLER 2.2 ENGINES MINIMUM WEIGHT IS 2350 LBS.. DODGE NEON MINIMUM WEIGHT 2500 LBS.. MAXIMUM LEFT SIDE PERCENTAGE IS 55.0%.

ROLLCAGE: THE FOLLOWING ARE ADDITIONAL REQUIREMENTS AND CLARIFICATIONS FOR THE INSTALLATION OF THE ROLL BARS. FULL ROLLCAGE REQUIRED. STEEL BOX TUBING, MINIMUM 2” X 2” X .120” MUST BE WELDED INSIDE THE CAR TO THE FLOOR ON EACH SIDE BY THE ROCKER PANELS. WHEN INSTALLING THE ROLLCAGE THE MAIN BAR REFERRED TO AS # 1 AND THE FRONT LEGS REFERRED TO AS # 2A AND # 2B MUST BE WELDED ON TOP OF THE BOX TUBING. THE MAIN BAR (#1) MUST BE VERTICAL (90 DEGREES) TO THE BOX TUBING. THE ROOF BAR REFFERRED TO AS # 3 MUST BE WITHIN 4” OF THE SIDE WINDOW AND/OR THE DOOR OPENINGS ON BOTH SIDES, AS WELL AS THE FRONT WINDSHIELD, WITH NO OFFSETS. THE CENTER SECTION OF THE ROLLCAGE MUST BE PER NASCAR DESIGN. ALL CARS MUST HAVE FRONT AND REAR HOOP BARS THAT ATTACH TO THE CENTER SECTION OF THE ROLLCAGE. A “PETTY” BAR (REFFERED TO AS 7A)  IS MANDATORY.

SUSPENSION:

ALL SUSPENSION PARTS MUST REMAIN STOCK OEM, UNLESS NOTED IN THE RULES. BUSHINGS MAY BE REPLACED WITH AFTERMARKET, PROVIDED THEY DO NOT ALTER THE ORIGINAL MOUNTING LOCATION (NO OFFSET BUSHINGS).

SPRINGS AND STRUTS: ALL STRUTS MUST BE OEM OR EXACT REPLACEMENT. STEEL STRUTS ONLY. NO ADJUSTABLE STRUTS OR CARTRIDGES ALLOWED. COIL OVER ADJUSTABLE SHOCK KITS ARE ALLOWED. NO COILOVER SHOCKS ALLOWED. SPRINGS MAY BE CHANGED (RACING SPRINGS ALLOWED) PROVIDED THEY FIT ONTO THE STOCK STRUT OR SPRING POCKET.  DOUBLE SPRINGS MAY BE USED. SPRING ADJUSTER CUPS ALLOWED. LEAF SPRINGS MAY NOT BE SHORTENED, BUT MAY BE HEATED. ADJUSTABLE SHACKLES ARE ALLOWED FOR LEAF SPRINGS.  NO JACKING BOLTS!

SHOCKS: AFTERMARKET STEEL BODY SHOCKS ALLOWED. NO ADJUSTABLE OR EXTERNAL RESERVOIR SHOCKS ALLOWED. SHOCKS MUST FIT WITHOUT ANY ALTERATIONS OR ADAPTORS. SHOCKS MUST REMAIN IN EXACT OEM POSITION/LOCATION.

REAR WHEEL CAMBER: FRONT WHEEL DRIVE (FWD) CARS, MAXIMUM REAR WHEEL CAMBER (POSITIVE OR NEGATIVE) WILL BE ¼”. MEASUREMENT TAKEN WITH A 24” CARPENTERS SQUARE PLACED AGAINST THE TIRE AND A TAPE MEASURE, MAXIMUM SPACE IS ¼”!

BRAKES: MUST REMAIN STOCK OEM AND BE OPERATIONAL ON ALL 4 WHEELS AT ALL TIMES.

STEERING: STOCK OEM STEERING FOR CHASSIS USED. COLLAPSIBLE STEERING SHAFT IS RECOMMENDED. IF COLLAPSIBLE STEERING SHAFT IS NOT USED, THEN THE SHAFT MUST BE MADE WITH AT LEAST 2 U-JOINTS AND INSTALLED SO THAT UPON A HEAVY FRONT END COLLISION THE SHAFT WILL DEFLECT TO THE SIDE.

SWAY BAR: THE FRONT SWAY BAR MAY BE CHANGED BUT MUST FOLLOW STOCK DESIGN AND MOUNTING POINTS.

PANHARD BAR: ON FWD CARS THE REAR PANHARD BAR MAY BE CHANGED AND/OR RELOCATED, ONLY ONE SINGLE STEEL BAR ALLOWED.

WHEELS: STEEL 7” OR 8” RACING WHEELS ARE MANDATORY. ALL 4 WHEELS MUST BE EITHER 7” OR 8”. 8” WHEELS MUST HAVE A MINIMUM 3”, MAXIMUM 4” (CENTERED HUB) OFFSET. 7” WHEELS MUST HAVE A MINIMUM 3”, MAXIMUM 3.5” (CENTERED HUB) OFFSET. ALL 4 WHEELS MUST THE SAME OFFSETS. WHEEL OFFSET IS MEASURED OFF THE INSIDE BEAD SEAT TO THE INSIDE MOUNTING FLANGE OF THE WHEEL. HEAVY DUTY WHEEL LUG/STUDS RECOMMENDED. STUDS MUST PASS COMPLETELY THROUGH LUG NUTS. WHEEL SPACERS ARE NOT ALLOWED.

TIRES: AMERICAN RACER 7.5 MC  704 COMPOUND,  TWO SIZES ARE AVAILABLE; 235/60 X 13 OR 235/60SH X 13.

ENGINE:

GENERAL SPECS: STOCK OEM FOR YEAR, MAKE AND MODEL OF CAR USED. MAXIMUM 2400 CC ENGINES. NO TURBO ENGINES ALLOWED. NO DUAL PLUG CYLINDER HEADS. 2 VALVES PER CYLINDER, SINGLE CAMS ONLY. ALL ENGINE PARTS MUST BE STOCK OEM.  ALL ENGINE PARTS INCLUDING STOCK REPLACEMENT PARTS OR AFTERMARKET PARTS WHERE ALLOWED MUST MAINTAIN STOCK OEM WEIGHT SPECS AND MUST BE COMPLETELY STOCK UNALTERED. THIS MEANS PARTS ARE NOT TO BE LIGHTENED IN ANY WAY. NO BORING, STROKING, PORTING, POLISHING, LIGHTENING, DEFLASHING, GLASS BEADING, SANDBLASTING, ABRASIVE CLEANING, CHEMICAL (ACID) MILLING, ETC., ALLOWED ANYWHERE IN OR ON ENGINE PARTS. NO INTERNAL PAINTING OR COATINGS (EX. TEFLON) OF ANY TYPE ALLOWED. ALL ENGINES WILL BE ALLOWED A MAXIMUM .030” OVERBORE. ONLY NORMAL OEM TYPE ENGINE BALANCING. DUE TO THE LIMITED AVAILABILITY OF 2.2 DODGE ENGINES, THE DODGE NEON WITH 2.0 MULTI VALVE SINGLE OVERHEAD CAM ENGINE WILL BE ALLOWED FOR COMPETITION WITH A WEIGHT PENALTY. 2.0 NEON MUST COMPLY WITH ABOVE RULES.

LOCATION: MUST REMAIN IN STOCK POSITION.

COMPRESSION: MAXIMUM COMPRESSION IS 10.0:1, CHECKED WITH THE “WHISTLER”. NO TOLERANCE ALLOWED ON MAXIMUM COMPRESSION!

CRANKSHAFT: MUST BE STOCK OEM, MAINTAIN STOCK STROKE .NO LIGHTENING OR KNIFE EDGING ALLOWED.

PISTONS: MUST BE STOCK OEM OR EXACT REPLACEMENT.

RODS: STOCK OEM ONLY. AFTERMARKET ROD BOLTS ALLOWED.

CAMSHAFT: AFTERMARKET CAMSHAFT ALLOWED. THE MAXIMUM LIFT AT THE VALVE WITH ZERO (0) LASH WILL BE .465”.

ROCKERS/FOLLOWERS: STOCK OEM ONLY. NO ROLLER ROCKERS/ROLLER TIPS EVEN IF STOCK OEM!  STOCK RATIO FOR ENGINE USED. ROCKER STUDS MAY BE OVERSIZED.

VALVE LIFTERS: MUST BE SOLID ONLY. NO ROLLER LIFTERS EVEN IF STOCK OEM!

CYLINDER HEAD: STOCK OEM PRODUCTION HEAD ONLY.

VALVES: MUST BE STOCK OEM OR DIRECT REPLACEMENT ONLY. NO PRO FLO OR POLISHED VALVES ALLOWED. AFTERMARKET STOCK DIAMETER VALVE SPRINGS  ALLOWED. STEEL VALVE SPRING RETAINERS ONLY.

VALVE JOB: MULTI ANGLE VALVE JOB PERMITTED. THE BOTTOM CUT OF THE VALVE JOB MAY NOT EXCEED 3/8” INTO THE VALVE POCKET. THE 3/8” BOTTOM CUT WILL BE MEASURED FROM THE TOP OF THE CUT UPON WHICH THE VALVE IS SEATED.

INTAKE MANIFOLD: MUST BE COMPLETELY STOCK AND UNALTERED.

CARBURETOR: THE HOLLEY 350 CFM, 2 BBL CARBURETOR PART # 0-7448 IS THE ONLY CARBURETOR ALLOWED. THE CARBURETOR MUST BE “STOCK OUT OF THE BOX”. ALL CARBURETORS MUST PASS NASCAR GAUGES. THE ONLY CHANGES THAT WILL BE ALLOWED ARE AS FOLLOWS; THE CHOKE PLATE AND SHAFT MAY BE REMOVED, JETS, POWER VALVE, ACCELERATOR PUMP CAM, AND ACCELERATOR PUMP DISCHARGE NOZZLES MAY BE CHANGED. IDLE HOLES MAY BE DRILLED IN THE BUTTERFLIES. NO OTHER CHANGES ALLOWED. NO RESHAPING, POLISHING, GRINDING OR DRILLING ALLOWED. NO ADJUSTABLE (JETTED) AIR BLEEDS OR CIRCUITS. GASKETS MUST REMAIN UNALTERED. NO “HP” PARTS ALLOWED. NO CHROME CARBURETORS.

CARBURETOR SPACER/ADAPTOR: ONE SOLID MATERIAL SPACER/ADAPTOR, MAXIMUM HEIGHT OF 1” PERMITTED. NO WEDGE SHAPE SPACERS/ADAPTORS ALLOWED. BOTH THE TOP AND BOTTOM SURFACES MUST BE PARALLEL. THE PORTHOLE MAY BE TAPERED TO MEET THE STOCK INTAKE OPENING. NO ADDITIONAL OPENINGS FOR THE INDUCTION OF AIR ALLOWED. ONLY ONE .075” GASKET PER SIDE OF SPACER ALLOWED.

FUEL INJECTION: MUST BE STOCK FOR THE YEAR, MAKE & MODEL OF CAR BEING USED (STRICTLY ENFORCED). THE MAXIMUM  FUEL INJECTION BORE ALLOWED FOR VOLKSWAGON IS 44 MM. NO MULTI-PORT FUEL INJECTION SYSTEMS.

AIR CLEANER/FILTER: THE AIR CLEANER TOP AND BOTTOM MUST BE METAL. ALL AIR CLEANERS ARE SUBJECT TO TRACK APPROVAL. NO DUCTS, BAFFLES OR ANYTHING THAT MAY CONTROL AIRFLOW ALLOWED ON OR IN THE AIR CLEANER ASSEMBLY. ALL AIR ENTERING THE CARB MUST PASS THRU THE AIR FILTER. NO AIR BOXES. A SHIELD MAY BE USED ON THE FRONT OUTER HALF OF THE ELEMENT, IF PLACE DIRECTLY ON THE ELEMENT. AIR CLEANERS MUST REMAIN UNDER THE HOOD

FUEL: MUST BE PETROLEUM BASED OR SYNTHETIC AUTOMOTIVE GASOLINE ONLY. GASOLINE SHALL NOT BE BLENDED WITH ALCOHOL, ETHERS OR OTHER OXYGENATES, PROPYLENE OXIDE, ANILINE OR ITS DERIVATIVES, NITRO-COMPOUNDS OR NITROGEN CONTAINING COMPOUNDS. NO ADDITIVES THAT ENHANCE HORSEPOWER! THE USE OF STOCK-UNLEADED FUEL SOLD AT LOCAL GASOLINE STATIONS IS ALLOWED. FUEL WILL BE TESTED.

FUEL PUMP: ELECTRIC FUEL PUMP ALLOWED, BUT MUST BE ENCLOSED IN A STEEL BOX UNDER THE CAR. FUEL PUMP MUST BE AS CLOSE TO THE FUEL CELL AS POSSIBLE. THE FUEL PUMP MUST BE TIED IN WITH THE OIL PRESSURE SWITCH, NO OIL PRESSURE-NO FUEL.

EXHAUST MANIFOLD: STOCK OEM ONLY. MO MODIFICATIONS ALLOWED. NO HEADERS ALLOWED. MAXIMUM OUTSIDE DIAMETER OF THE EXHAUST PIPE WILL BE 2 ½”. EXHAUST MUST EXIT 6” PAST THE DRIVER’S SEAT, UNDER THE CAR.

MUFFLERS: MANDATORY! SEE GENERAL RULES.

OIL COOLERS: ARE PERMITTED.

IGNITION: STOCK OEM. THE USE OF AN AFTERMARKET HALL EFFECT SWITCH WITH MODULE DISTRIBUTOR IS ALLOWED ON CHRYSLER & VOLKSWAGON PRODUCTS TO ELIMINATE THE COMPUTER SYSTEM.

BATTERY: MAY BE RELOCATED. THE BATTERY MUST BE SEPARATED FROM THE DRIVER IN AN APPROVED MANOR. IF INSIDE THE DRIVER COMPARTMENT, BATTERY MUST BE IN A MARINE TYPE CASE.

DRIVETRAIN:

TRANSMISSION/TRANSAXLE: STOCK OEM 3, 4 OR 5 SPEEDS. ALL GEARS MUST BE IN WORKING ORDER. DIFFERENTIAL MAY BE LOCKED.

CLUTCH/FLYWHEEL: STOCK OEM STEEL ONLY. FLYWHEEL MUST REMAIN UNALTERED. NO LIGHTENING ALLOWED. A 1” HOLE MUST BE DRILLED IN BELL HOUSING OVER THE CLUTCH FOR INSPECTION.

DRIVE SHAFT/HALF SHAFTS: STOCK OEM STEEL ONLY.

REAR END: STOCK OEM FOR MAKE AND MODEL. REAR ENDS MUST BE EITHER “OPEN” OR “LOCKED”. NO POSI, LIMITED SLIP OR RATCHET REARS OF ANY TYPE ALLOWED.

ADDITIONAL INFORMATION :

MINI STOCKS MUST ALSO COMPLY WITH THOMPSON INTERNATIONAL SPEEDWAY GENERAL/SAFETY RULES.

THOMPSON INTERNATIONAL SPEEDWAY RESERVES THE RIGHT TO SWAP AMONG COMPETITORS OR ISSUE ANY ELECTRICAL COMPONENT IN THE CAR, PRIOR TO ANY RACING EVENT. FAILURE TO COMPLY WILL RESULT IN THE LOSS OF ALL EARNED POINTS.

BECAUSE MINI STOCKS ARE A HOBBY DIVISION WITH A VARIETY OF MANUFACTURERS, A WEIGHT PENALTY RULE WILL BE INSTITUTED AFTER THREE WINS. AFTER THREE WINS AND EACH ADDITIONAL WIN, A 25 LBS WEIGHT PENALTY WILL BE ADDED TO THE MINIMUM CAR WEIGHT.     

                              TECH QUESTIONS CONTACT MIKE KUN AT MSK630@AOL.COM

Sources:  Russ Dowd/Thompson International Speedway PR
Posted:  November 27, 2003