Path Valley Speedway
717-349-7111
17911 Dry Run Road
Spring Run, PA 17262
2025 4 Cylinder Thunder Car Rules
Posted 11/16/23
Legend tires will NOT be allowed in 2024
No convertibles, four-wheel drive, VW, Saab or Jeep type vehicles allowed. Maximum stock wheelbase of 105”.
Self-starting vehicles must start on their own for the initial green of their race or they will start last. Heavy duty tow chain/cable is mandatory on both bumpers.
Transponder Location - 12" maximum in front of center strut bolt on EITHER side.
ROLL CAGE AND BRACING:
Minimum of 1 ½” OD - .095 wall tubing must be used. Roll cage must be welded securely to frame with a four-point design. Uni-body cars are allowed framed bracing but no cross bracing. Roll cage must extend from front of door opening, to the rear of the front door opening. 2 bars are allowed to be welded to plates (4” x 4”, 1/8” thick) on the trunk floor area, between the rear seat and the tail-light mounting (inside the body). Forward bars are allowed to come to the front of the radiator support on vehicles equipped with strut type suspensions. On cars without strut type suspension, the bars may be mounted to the inner fender above the upper control arm. Vehicles in this class may not have any form of sub-frame (front or rear), tied into the roll cage. If rub rails are used, they must be placed against the body between the front and rear fenders. All rub rails are to start and end inside the body panels. Rub rails will not have any sharp edges. Removable rails are permitted as long as they bolt to the roll cage on the inside of the body. Maximum diameter is 1 ½”. Minimum diameter is 1”. A minimum of three, maximum of five, 2/8” rebar to run from top of roll cage bar to dash tie-in bar. No smaller than 1” square window screen across entire windshield area.
BODIES:
Up to 1995 body style is permitted.
No sheet metal allowed except doors. Doors can be skinned. Driver's door must have a 16" x18" plate between door and roll cage if the door is skinned. Cars must be strictly stock. No cutting, chopping or shortening allowed, except cutting of driver's interior door panel for roll cage clearance. No cutting, chopping or shortening of roofs. Trunk and hood lids may also be stripped. Complete hood must be kept in place by secure quick release pins. Body metal must be in place at start of race. All glass and lights must be removed. All doors must be completely welded or bolted shut. No tech screws are to be used, rivets only. No after-market spoilers of any kind are allowed. Stock metal only. Bumpers should be tied into body panel by steel plates to avoid getting hooked and torn off. No fiberglass bumper allowed. Both bumpers must have a way to be hooked and towed off track easily – must be easily seen and accessed. All bumpers must be securely fastened to vehicle and welded solid to chassis so that it will not be knocked off the car on impact. NO SHARP EDGES! Loss of any body part, including bumper, the vehicle must leave the track immediately. No holes allowed in hood. All holes in front and rear firewalls must be covered. Raked, modified roof lines are subject to removal of upper air shield; unmodified roof lines may use upper air shield. Must maintain stock body lines. Racing weight will be 2350 lbs.
INTERIORS:
Interior of car, including doors, must remain intact except for driver's inside door panel, which can be cut to accommodate door bars. Rear seat cushions must be removed. Rear seat shelf must be left in as fire stop. The stock steel unaltered floor pan, firewalls, trunk, trunk floor and all wheel wells must be retained. Front and rear firewalls must be sealed. Seat must be aluminum racing seat. Back of seat must be tied into roll cage. Five point safety harness required. No built up interiors of any kind. No mirrors allowed. All non-factory holes must be filled in with metal. No windshields allowed. No plexiglass anywhere on body. Lexan may be used for visors, maximum of 6”, and rear side windows only.
SUSPENSION:
No modifying of the suspension. Parts must remain absolutely stock for that make and model of car. Only rubber spacers allowed. No other spacers (example: lumber, metal chains, etc.), may be used to alter suspension of the car. Changing of right front spring only to heavier spring is allowed, safety chain allowed on right front spring only. No racing suspension or screw adjustable springs allowed on car anywhere. No cutting or moving of components. Shifting top of strut is allowed as long as it stays within original strut tower. Cutting the strut tower for adjustment is allowed.
TIRES AND WHEELS:
All stock wheels must be reinforced to prevent their loss. Tires must be AMERICAN RACER TIRES ONLY. No racing DOT, truck, studded, recap, racing, or trick gum ball tires of any kind permitted. No aluminum, trick or bead lock wheels allowed. Steel wheels, maximum 8” allowed. 2", 3” and 4” rim inset or rear spacing permitted. 60 or 70 series tires with 13” or 14” rim diameter. Racing wheels allowed, 8” tread width on tires with a ½” tolerance measured from edge of tire tread. Tire grooving is allowed. Maximum tire size is 205-70-14. Bead-lock may be used on right side, front and rear, only.
Path Valley Speedway will be allowing the American Racer 235/60 13" tire in the Thunder Car division. American Racer is working with Path Valley in conjunction with BDR Racing Products to provide this tire at a discounted price. The tires must be purchased through Bob Dunn at his shop or at the speedway. The tire will come in a short height and regular height dimension. Contact Bob Dunn at BDR Racing for more information. No grooving or siping.
ENGINE:
OEM FORD PARTS ONLY!
THERE MUST BE A BUNG HOLE IN THE OIL PAN ON DRIVER'S SIDE, 1 1/2" OR BIGGER.
The engine must be strictly stock for that make and model and in its original mount, no motors mix/match. No stroked motors. Solid motor mount allowed in its original mount position. Maximum .040 overbore. No Aluminum Heads. Any factory headers allowed. No shaving head, porting, polishing, turbos, or engine changing. Replacement cams must meet track specifications. Adjustable cam pulleys are permitted. Under drive pulleys are permitted to run water pump. Valve sizes must remain stock. Pistons must be flat top type with stock profile and stock wrist pin height. No polishing or cutting and balancing or rotating assembly. Aftermarket 5.2 rods NOT allowed. RODS MUST BE STOCK RODS.
EXHAUST
A single exhaust system will run inside the car, through a race muffler, and exiting the passenger door. The exhaust will exit the car in a round pipe of 3” inside diameter. Exhaust that passes anywhere through the driver compartment must be completely covered by metal. There must be a 2" space between the exhaust pipe and the covering metal. The exhaust system must be intact on any vehicle taking the checkered flag. Exhaust must exit to side of car – not to the ground. After market headers are allowed; 3" exhaust must exit through passenger door. A missing exhaust system from any car that takes the checkered flag is dropped from position and scored as the last vehicle on the lead lap.
IGNITION:
No after-market components or MSD boxes. Must have master disconnect switch clearly marked on rear shelf, behind driver near battery.
DRIVE TRAIN:
Stock rear end, transmission, clutch and fly wheel only. Stock drive train only. Stock rear housing for make and model of car. Rear may have spider gears welded. No spools or any kind allowed. Stock flywheel weight limit of 15 lb minimum in manual transmission cars. 1” x 3” inspection hole in bottom of bell housing required. Miners belt on bell housing is mandatory. Two driveshaft hoops mandatory and must completely encircle the driveshaft. Loops must be no more than 8” from rear of front universal and 8” from front of rear universal.
CARBURETOR CARS:
Stock 250 carb to 500 Holley carb permitted. No cutting of carb except choke assembly may be removed. No carb spacers. NO FUEL INJECTION.
FUEL CELL (GAS TANK):
Maximum 15 gal fuel cell. Fuel cells in trunk must be enclosed with metal. Racing fuel is allowed. No alcohol or any additives allowed. Fuel testing may be done at the discretion of the track tech personnel. If fuel is found to be illegal, you will lose pay-out and points for that race. You will also be fined $25.00. Any electric fuel pump will have a safety switch and safety oil switch. Anyone running an alternator must have a kill switch for alternator. All switches must be clearly marked and reachable from driver’s seat.
BRAKES:
REAR DRUM BRAKES ARE PERMITTED.
4 wheel brakes MUST BE IN GOOD WORKING ORDER AT ALL TIMES. Stock brake system in stock mounting position must be used for make and model of car being used. No after market in-line proportioning valves allowed.
SAFETY:
Approved helmet (SA2010) with face shield is mandatory. Neck braces are required. Race approved, 5-point minimum racing belts in good condition with one release for all belts required. Safety belts must be mounted to roll cage. Fire resistant driver’s suit is mandatory and must meet track specifications. Fire extinguisher, 12 oz. minimum, is mandatory. It must be securely mounted for quick access. Race approved driver’s side window net is mandatory. All weights must be securely bolted with lock nuts, double nuts or nuts with cotter keys. Weights must be painted white and have car number painted on them. Race seats are mandatory. All seats must be mounted to roll cage, located in front of doorpost and to the left of drive shaft tunnel.
LETTERING:
All cars must be presentable in bodywork, craftsmanship and paint. The car numbers must be clearly displayed on the roof and BOTH doors at all times. Number must be no less than 18” tall and 2” wide. If a letter is used, it must be 9” x 2” minimum. A plate with a minimum 6“ number will be required on the right-hand corner of headlight. No reflective lettering. Lettering must be outlined and legible (if the scorers can’t read your number, you won’t be scored).
MISCELLANEOUS:
Battery may be moved inside of car and enclosed in a metal box securely fastened, in a metal framework, to the car. No bungee straps. Any loss of a wheel requires that you immediately leave the track. Rupture of gas tank and/or loss of gas receive immediate black flag. No horns or 2-way radios.
Anything not covered in these rules will be left to the discretion of the tech and track officials, without recourse from drivers or owners. Safety infractions can be cause for a car to be kept out of competition until they have been corrected. The preceding rules are subject to revision and will be judged accordingly.
UNLESS THE RULES SAY YOU CAN – PLEASE DON’T!
