Welcome to Chowchilla Speedway’s 2020 racing season. We are extremely excited to get back on the track! Throughout this rule book, we will be covering the regulations for the Mini 4 races. If you wish to race, then you must comply with the following rules. Also, no performance parts are acceptable on your vehicle’s engine!
MODELS
- No 4 doors.
- No station wagons.
- Must be small sedan.
ENGINES
- Maximum 1600cc.
- Any compression ratio.
- Intake manifold must remain stock. (No Alterations)
- All smog may be removed.
- No roller lifters.
- Must run stock ignition.
- Stock rods only.
- NO offset bushings in connecting rod wrist pins.
- Stock type pistons only.
- Must run stock size valves with single springs.
CARBURETOR
- One stock 2 barrel only.
- May remove butterfly.
- May change jets.
- 2 return springs.
- Must run air filter.
- Gas only.
- Must change from cable to rod.
EXHAUST
- Must run muffler.
- Must meet 95DBs at 100 feet.
- Must run stock exhaust manifold.
- No grinding, porting or polishing.
- All exhaust pipes must run under car and exit behind driver.
FUEL
- Stock mechanical fuel pumps recommended. If you run electric fuel pumps you must have a shut off valve.
- GAS only.
- Must run fuel cell.
- Cell must be securely fastened inside of trunk.
- Must have roll over valve.
- All fuel line running inside of drivers compartment must be in steel sleeve.
- Cell must be in center of trunk in steel container.
BODY
- No excessive gutting.
- Must remain stock appearing.
- All body parts must remain in stock location.
- Fire wall must remain in stock location.
- No fiber glass, aluminum.
- Doors must be bolted or welded.
- Bumpers must remain stock may run tubing behind for support.
- Bumpers must be plated to fenders.
- Must remove all glass and plastic may remove dash and replace with fabricated dash.
- May take out stock steering and replace with steel shaft.
- Must have readable numbers on both doors and on roof.
- NO Rear view mirrors.
- Windshield must be removed and replaced with screen or bars.
BATTERY
- One battery only.
- Battery must be securely mounted and in an approver container .
- A battery kill switch is to be mounted on left side of drivers compartment and clearly marked yellow or red.
ROLL CAGE
- A full cage is mandatory.
- 1 ½ OD .95 wall.
- Must have 3 door bars on both sides.
- Gussets are required on all connections in main cage.
- Must run bar in trunk for fuel cage protection.
- Front loop OK.
- All bars close to driver must be padded.
- Seat must be mounted to cage.
- Cage must be mounted to floor with 4×4 plate.
TRANSMISSION
- Stock trans only.
- Stock clutch.
- Stock fly wheel.
- Must have scatter shield.
- Must have working forward reverse and neutral.
DRIVE TRAIN
- Must run all stock parts.
- Driveline must be painted white and have 2 safety loops 1 in front and 1 in the rear.
- Any toe in or toe out is allowed.
- Stock shocks only and must be in stock location.
- Cutting front springs ok (may use spacers).
- Adjustable front struts ok.
- Camber may be altered.
- May add or subtract leaf springs.
- May have shackle adjuster.
- Wheel base must remain stock +/- 1.5 inches.
WHEELS AND TIRES
- Wheel spacers ok.
- 1 inch lug nuts mandatory.
- 13inch or 14inch rims only 7inches wide maximum.
- Must run DOT approved passenger car tires only.
- No mud grip or aggressive tread.
- Grooving allowed.
- No air bleeders.
REAR ENDS
- Must run stock rear end for make and model.
- May lock up.
BRAKES
- Must run stock brakes.
- After market brake pads ok.
- After market master cylinders ok.
- 3 wheel brakes ok.
OTHER STUFF
- Must have at least single layer fire suit. (RACING)
- Must have Snell 90 or better helmet.
- Gloves and neck brace recommended.
- Aluminum racing seat mandatory.
- Window net mandatory.
- Fire extinguisher must be mounted in car.