1974 NASCAR International Stock Car Racing Rule Book Late Model Sportsman Division Section 20B-11 -- Carburetor Air Cleaner

a. Ram air intake not permitted.

b. Air cleaner must be a minimum of 3" from the fire wall. The fire wall must be flat in the area of the air cleaner. Absolutely no extensions or baffles between the air cleaner and the fire wall.

c. Maximum opening of the cowl induction area in the fire wall shall be 95 square inches. Maximum width of the air cleaner opening cannot exceed the maximum width of the allowable opening in the cowl.

d. It is permissible to have one 1" bracket on each side of the rear of the air cleaner. The brackets must be attached to the engine. No additional brackets or supports permitted.

e. Absolutely no baffles or panels from the engine or air cleaner to the fire wall. Air cleaner must maintain minimum 3" opening all the way around. Air cleaner cannot be flared on lower backside to close up area to the manifold. No baffles or panels permitted from the air cleaner to the manifold.