Cast iron blocks are mandatory. 358 cubic inch maximum displacement.
Flat top pistons only - no domes or dishes. Zero deck height.
Maximum compression ratio of 10.75 : 1 as checked by whistler guage
Maximum 3.5 inch stroke. Weight of crankshaft not to be less than 46 lbs.
Cast iron heads of stock configuration mandatory. No raised intake runners or
spread port exhaust. Porting into runner 3/4 to match manifolds is allowed. No
port and polish, Ford Windsor heads may have the exhaust ported except the valve guides. All GM heads factory and after-market must have 23 degree valve angle.
Intake port may be matched to the intake manifold or gasket, not to exceed a
depth of 3/4. Intake valve may not exceed .060 inch over stock valve size i.e.
2.020 stock - 2.080 maximum. Intake seats may be cut back under the valve seat
with a maximum angle of 75 degrees. No grinding or acid etching under the valve seat will be permitted.
Exhaust port may be matched to gasket or header, not to exceed a depth of 3/4. Exhaust valve size may not exceed .025 inch over stock size, i.e. 1.600 stock - 1.625 inch maximum> Exhaust seats may be back cut under valve seat with a maximum angle of 75 degrees. No grinding or acid etching under the valve seat will be permitted.
Grinding in the combustion chamber will be permitted. Welding in the combustion chamber will be permitted for repair purposes only. No welding to reshape the combustion chamber. The combustion chamber will be defined as beginning with the head gasket area and ending at the top of the valve seat. This is to allow the participant to meet the 10.75 to 1 compression limit and allow competitor valve jobs to be performed to meet specifications outlined in intake and exhaust specifications. Selinsgrove Speedway whistler box will be used to check compression. 10.8 is acceptable. If box reads 10.9 or higher your engine will be declared illegal.
No modification allowed to heads that would allow the use of down nozzles or multiple spark plugs per cylinder.
Must be naturally aspirated. Fuel injection or carburetion allowed. Timed and/or electronic fuel injection units are prohibited.
No V-6 engines.
No titanium, plastic or carbon fiber components (titanium valve spring retainers
will be permitted).
Piston must be flat top with the top of the piston square to the bore of the cylinder. WINGS:
FRONT WINGS - Maximum size to be 6 square feet total with a maximum width of 36 inches. Side Panel maximum size is 12 inches x 26 inches with a 1/2 inch maximum turnout at 90 degrees from panel, and must be mounted 90 degrees to foil. A 1-inch wickerbill permitted. Center foil must be square or rectangle in shape with all four corners of foil 90 degrees.
TOP WINGS - Maximum size of 16 square feet and must be one piece. The deepest point allowed on the top surface of the wing will be 2-1/2 inches measured from the front edge to the back edge of the foil. Center foil must be square or rectangle in shape with all four corners of the foil at 90 degrees. Center foil may have 1 inch maximum wickerbill added to back top edge of foil. Side boards must be one piece maximum size of 66 inches long and 30 inches wide with 1 inch x 1 inch turn out on front (leading) top and bottom. Rear edge of panel may have a maximum turn out of 1 inch x 2 inch to the front of the panel. Turn out must be 90 degrees from flat portion of the side panel. Side board top 2/3 of panel must have 2 corners each 90 degrees no variance. Front edge of side panel cannot be behind the lead edge of foil. Side boards must be mounted 90 degrees to center foil and parallel to each other. No split wings or bi-wings. Side wings, rear wings or rudders are not allowed.
Wings can not be adjustable from cockpit. No car will be allowed to compete without a top wing. Wings cannot be replaced on track during a red flag or in work area. Car must go to the pit area to replace either wing. Wings must be fabricated of metal alloy only. No Fiberglass, plastic, or carbon fiber.(Except for 6 inch maximum cover on leading edge of foil). No part or a wing can mounted past outside edge of the tire.
FUEL:
Methanol only according to Federal Standard of Purity, Grade A or AA.
No additives of any kind including top lube will be allowed in the fuel.
WATER TEST WILL BE USED TO CHECK FUEL.BODY:
Body should give the appearance of completely covering the car's frame and should be fully painted. The hood or cowling need not enclose the sides of the engine. One piece tail and fuel tanks permitted, must be streamlined. No side foils, rudders or panels are to extend beyond roll cage on any side. No body pieces to extend beyond or underneath front torsion tube except hood.
MISCELLANEOUS:
No radios (one way or two way) or other means of electronic communications are permitted.
No mirrors of any type may be utilized.
No drilling of any bolts, fasteners or heim ends. No hollow fasteners allowed.
SUGGESTED SAFETY EQUIPMENT:High back seats.
Knee pads or padding around steering.
Driving uniforms that are flame retardant with a minimum of two layers. Flame retardant driver's underwear, head sock, gloves, foot socks, and shoes.
Neck collars.
Windshield screens with a minimum of .090 screening.
Head rest padding.
Right headnet or support equipped with quick release capabilities.
Arm restraints.
Minimum of 10 inch vertical opening on right side of cockpit.
Kill switch in reach of driver.
Fuel shut off valve.
No pop rivets to fasten wings, bumpers or nerf bars to chassis. No
aluminum rear bumpers or nerf bars, nerf bars to be
inside of tires.
Minimum 3 inch wide seat belts, mounted to frame with bolts or looped over frame tubes, belts traveling through bottom of seat. Minimum 3 inch wide shoulder harness, double over shoulder, military shoulder straps with anti-sub crotch belts. Harness to go over a horizontal tube located no less than 3 inches below the top of the driver’s shoulders.
Full face Snell approved helmet.