2013 STOCK FOUR RULES
Only the modification of items listed in this section may be changed. All others must remain stock. Any alteration not approved by track officals will be considered illegal. All competitors will be required to have in their possession at the track an official manual describing make, year and model of body being used plus stated wheelbase from the factory. Engine specifications are as follows; Cam design, valve sizes, cubic centimeters or cubic inches, bore size and stroke of engine used.
Should a competitor not produce an offical manual to prove legality in the case of a protest, the car will be declared illegal at the discretion of the tech offical(s).
Open to all American and Foreign made 4 cylinder sedan cars and pick-up trucks having factory wheelbase minimum of 90 inches. Sports cars, convertibles or special production high performance vehicles NOT PERMITED. No all-wheel steering cars allowed.
1) All body and body parts must be neat in appearance. Cars with missing or heavily damaged parts will not be able to compete until properly repaired.
2) Stock bodies, aftermarket and homemade bodies allowed. Must have either stock or aftermarket front nose covers. Must have a rear bumper. Rear of car or truck must be closed.Aluminum panels allowed.
3) All glass, lights, burnable material and exterior trim must be removed. Tailgates must be on trucks and must be securely fastened in closed position. Tailgate must be equal to bed sides in height. Fabricated bed sides must be a minimum of 15 inches above top of frame rails.
4) No tilting of tailgates. Bed covers allowed. May be covered with aluminum.
5) Maximum spoiler height 5 inches of upright material, lenght may not extend past body sides. 2 spoiler ends allowed. Maximum height 6 inches, maximum overall lenght 12 inches.
6) Wheel openings may be cut for tire clearence. Inner fenders may be removed.
7) Stock hoods and trunks may be altered to fit aftermarket nose pieces.
Dash is optional. Boxed interior allowed.
9) Floorboards – front and behind seat must be complete from side to side of body and sealed. Floor panels that are rusted out or damaged beyond repair may be replaced with a a minimum of 20 gauge steel. No Aluminum! Floorboard must remain in manufacturer’s original position. Car cannot be tunneled. Floorboard on right side of driver may be notched to raise exhaust pipe above floor pan, but must be completly covered for safety reasons.
10) Firewall must be stock and in original location. Firewall must be complete and from side to sideand must seal driver compartment from engine compartment. Rear firewall must seal fuel cell and battery from driver compartment. Rear firewall may be constucted of Aluminum with a minimum thickness of .040″. Fuel cells are MANDATORY and mounted securely.
11) Hook up chains MANDATORY front and rear outside of bumper covers.
12) Lexan front visor maximum of 6 inches from top of windshield opening allowed.
13) Lexan door glass permitted, but not to exceed 16 inches in length at bottom door edge.
14) All cars must have a minimum of 3 bars mounted in front of driver with a minimum thickness of 3/8″ and securely mounted. MANDATORY!
15) Ground effects and/or skirts allowed.
FRAME AND SUSPENSION…..
1) Framework must be listed as standard production for body used. Framework must must be in standard location for body used. No offsets permitted ! Support for rear unibody framework ONLY may be used to extend either over or under axle from rear of unibody to rear of car, but should in no way effect suspension joints or movement.
2) Suspension must be made of same design as originally manufactured. Suspension joints may be reinforced, but no change in location or operation.
3) Front Suspension – Solid bushings allowed. No offset bushings. Camber plates allowed.
4) Rear Suspension – Pivot points must remain stock and in stock location. NO MODIFICATIONS !
5) Control arms on straight axle rearendsmust be OEM for car used. Solid bushings allowed. No offsets bushings!
6) Independent Suspension – Lower control arms may be altered to achieve “0″ Camber on rear wheels. Plus or minus 1 degree tolerance from 0 allowed. NO MODIFICATIONS TO PIVOT POINTS ALLOWED!
7) Stock type shocks and struts ONLY! NO adjustable racing shocks or struts allowed. Shocks must be in stock location! NO MODIFICATIONS!
Adjustable cups allowed on front and rear. May be located on top or bottom of springs. Lowering blocks allowed on rear.
9) Cars manufactured with coil spring suspension must remain coil spring. Same for leaf spring cars.
10) No screw jacks allowed.
TRANSMISSION AND DRIVELINE…..
1) Differential and/or housing must match manufacture of car used.
2) Transmission must be OEM for car used. Gear boxes must have all forward and reverse gears in working order.
3) Transmission and rearend……..any ratio.
4) Rearend may be locked. Spools allowed.
5) Driveshaft must have safety loop. Drive shaft must be painted white.
6) Flywheel, clutch disc, pressure plate and bolts must weigh 1.25 pounds per 100 cc’s. Release bearing will not be weighed. No aluminum or trick type flywheel or pressure plate allowed. No drilling of flywheel. Single full clutch disc only. Flywheel and pressure plate bolt pattern must match.
1) Dual overhead cams allowed.
2) Engine must be standard production, 4 cylinder from manufacturer of car / truck being used. No crossing of manufacturer lines. No special, limited production or high performance engine or parts may be used, except where allowed in rules. No rotary engines allowed!
3) Head must match block used. 3 angle valve job allowed. No cutting below seat area. No enshrouding in combustion chamber. Stock replacement stainless steel valves permitted. Flat milling allowed. Screw in studs allowed.
4) All engines must be in stock location.
5) Stroke must match block used, .011 inch tolerance.
6) Bore and stroke must agree as manufacturer of engine intended. Maximum overbore .060 inches with .015 allowance for wear.
7) Reduction pulley on crankshaft allowed.
Camshafts – Solid or hydraulic maximum .425 lift @ valve, no added weight. Over .425 lift @ valve add 100 pounds. Stock rocker arms for engine used.
9) Degree pulleys allowed.
10) Valve size must be standard for engine, plus .009 inches tolerance.
11) Standard production cylinder head. Head must match block used. Hydraulic heads may be converted to solid.
12) No porting or polishing allowed. No gasket matching.
13) Intake must be stock for engine used. No modifications. Adapter and gasket maximum thickness 1.25 inches, No tolerance.
14) Bottom end must remain stock. Aftermarket rod bolts and balancing allowed.
15) Crankshaft: stock only. No aftermarket. May be balanced, stock stroke only. No lightening, no knife edging. Rods: any steel. No titanium. May be reworked.
16) Pistons – Any flat top, No cutting, milling or modifying pistons allowed.
17) Any fan or radiator.
18) Headers allowed.
19) Single 2 barrel carburetor only. Motorcraft, Rochester or STOCK replacement Weber allowed. Holley 350 cfm w/ air horn and list number.
20) Fuel Injection systems – Factory fuel injection for car / engine used. Must remain STOCK!!!!!!!!! Aftermarket Injectors allowed. No adjustable fuel pressure regulators.
21) No super charger, turbo charger, nitrous or boost device permitted.
22) One ( 1 ) fuel pump only. No fuel lines in drivers compartment. Electric pumps must be wired through oil pressure switch.
23) Gasoline for fuel only. 24) Stock Ignition. No modifications allowed. May lock advance mechanism.
1) Car must have all four wheel brakes in good working order at all times. No adjustable valves or pedals, stock or otherwise. No line restricting device or any other aftermarket parts will be allowed. Four wheel factory disc allowed.
1) Weight requirement is one pound per cc including overbore. CC’s must be posted on right rear of hood. MANDATORY! Registered cars with weights not posted on hood will be weighed at 2500 pounds. NO ACCEPTIONS!
2) Minimum weight is 2000 pounds.
3) Camshafts over .425 lift add 100 lbs.
4) Holley 350 cfm carburetor add 75 lbs.
5) Track reserves the right to add weight to any car to keep class competitive. Weight placement determined by track.
Toyota 3tc must weigh 2300lbs.
TIRES AND WHEELS….
1) Steel wheels only. Maximum wheel width 8 inches. Any offset. Large studs recommended.
2) Wheel spacers allowed. Maximum thickness 1/2 inch. One per wheel.
3) Any 8″ wide racing tire or any 8″ wide DOT approved street tire.
4) Grooving permitted, but not to be grooved at track!
5) No treating or prepping tires at track. THER ARE TO BE NO TIRES LEFT AT THE TRACK UNDER NO CIRCUMSTANCES!