1. Front Wing – Maximum size to be 6 square feet total with a maximum width of 36 inches. Center Foil must be square or rectangular in shape with all four corners set at 90 degree angles. 12 x 26" maximum side panels with ½ inch maximum turnout at a 90 degree angle from foil. A 1 inch wickerbill permitted at back edge of foil.

2. Top Wing – Maximum size to be 16 square feet, must be one piece. The deepest point allowed on the top surface of the wing is 2 ½ inches measured from the top of the wing to the bottom edge of the 1-inch turn up (wickerbill) at the rear edge. Center Foil must be square or rectangular in shape with all four corners set at 90 degree angles with no variance allowed.   Top wing side boards maximum size, 66 inches long and 30 inches tall. The top 2/3’s of each top wing side panel shall consist of only 2 corners. Each corner shall be set at a 90 degree angle with no variance. This portion of the side panel’s leading edge cannot be behind the center foils leading edge. Panels must be of one-piece construction. Panels must be fabricated flat. Turnouts on all edges of the wing must not exceed 1" x 2" and must be orientated at a 90 degree angle to the flat portion of the side panel. Side boards must be mounted square to the center foil and parallel to each other with a ¼ inch variance allowed.

3. Side wings, rear wings or rudders are not allowed.

4. All wings must be fabricated of metal alloys only, no fiberglass, plastic or carbon fiber. No split wings or bi-wings.

5. Wings cannot be adjustable from cockpit.

6. No car will be allowed to compete without a top wing.

1. Tire compounds legal for competition at Williams Grove Speedway will be Hoosier SC12, SC15, SCRD15, SC25, SC55.

2. Left rear tire maximum section width (sidewall to sidewall) is 19 ½ inches.

1. A sprint car is defined as a racing vehicle of single seat design, built upon a racing chassis and mounted on four racing wheels. No rear engine cars or aluminum frames allowed. No box tubing frame rails. Driver’s compartment shall be separate from the engine by a firewall of suitable material.

2. Allowable wheelbase of 85 to 90 inches.

3. Steel front axles only. Rear axles may be aluminum.

4. Must have front and rear brakes in working order.

5. Maximum wheel diameter 15 inches. Left rear tire maximum section width (sidewall to sidewall) is 19 1/2 inches. Maximum right rear wheel width is 18 inches. Wheel width is measured where the tire seats against the wheel. For wheels with bead locks, the measurement is taken with the bead lock installed. No plastic wheels. Wheel covers must be securely fastened.

6. Titanium or carbon fiber brake rotors are not allowed, must be steel or aluminum.

7. No cockpit adjustments permitted including adjustable shocks, weight jackers or wings.

8. Nerf bars, which offer adequate protection in the event contact with another car, are mandatory. Nerf bars and bumpers must be made of steel and be at least one-inch in diameter. Nerf bars must be bolted or roll pinned to the vehicle. No pop rivets may be used to fasten nerf bars, bumpers or wings. Nerf bars may not extend past outside of tires.

9. Approved fuel bladder required. No carbon fiber fuel tanks.

10. Hoods are mandatory during racing.

11. Total weight of car and driver may not be less than 1,500 pounds. Weigh in to be after any event or qualifying. Weight to be measured as car comes off of the track in the condition that it took the checkered flag. Any added weight must be securely fastened.

12. All cars must use either a driveline strap or a driveline hoop restraint constructed of .065 steel either welded or bolted to the chassis. Metal hoop restraints must react positively to magnet testing. The rear cross member used for mounting the steel driveline hoop must be constructed of .083 steel.

13. Drag links must utilize 4130 steel of at least 1" in diameter and a minimum wall thickness of .058. Tie rods and heim ends must be made of steel only. A magnet must stick at all times. No swedging of the tubing will be allowed.

14. Drag link must be tethered to the frame with nylon webbing of at least 1 inch wide.

15. No drilling of any bolts, fasteners or heim ends. No hollow fasteners allowed. 

1. Any cast iron block, V-8 engines only.

2. 358 cubic inch maximum displacement.

3. Maximum stroke 3.5 inches.

4. Flat top pistons only, no domes or dishes. Zero deck height.

5. Maximum compression ratio of 10.80:1 as measured by whistler gauge.

6. Cast iron heads of stock configuration mandatory. Stock OEM valve guide angle. All Chevrolet OEM heads and Chevrolet aftermarket heads must have a 23 degree valve guide angle, plus or minus 1 degree. All Ford OEM 302 Boss heads and Ford aftermarket Type "N" heads must have a 10 degree valve guide angle, plus or minus 1 degree. All other Ford heads must have a 20 degree valve guide angle, plus or minus 1 degree. Other manufacturers contact speedway management for valve guide angles. Port and polish of heads permitted. No raised intake runners or spread port exhaust. No modification to push rod area on intake port.

7. No modifications permitted to heads that would enable the use of down nozzles or multiple spark plugs per cylinder.

8. Must be naturally aspirated. Fuel injection or carburetor allowed. Timed and/or electronic fuel injection units are prohibited.

9. No titanium crankshafts. Steel rods only. There must be a 3/4 inch inspection hole in the left side of the oil pan opposite the number one rod journal or the oil pan will be removed for inspection purposes.