1974 NASCAR International Stock Car Racing Rule Book Grand American Cars Section 20A-6 -- Ground Clearance

a. Minimum of ground clearance of 6 1/2 inches on the left side, measured from the lowest part of frame or body, and not more than 2 inches higher on the right side, measured from the lowest part of frame or body. Oil pan minimum ground clearance 5 inches; exhaust pipe minimum ground clearance 4 inches. (Use of any special device to obtain minimum ground clearance will subject the car to disqualification because such device may become dislodged while car is in motion, thereby lowering the car below the approved ground clearance.) Violation of this rule will result in fine.

NOTE: For AeroWarriors.com users, Grand American Cars are governed by the same rules as the NASCAR Grand National Championship Division, with the exception of this Section, and the following:
Section 20A-1 -- Competing Models
Section 20A-2 -- Engine
Section 20A-3 -- Engine Mounts
Section 20A-4 -- Minimum Weight
Section 20A-5 -- Frames
Section 20A-7 -- Wheels