1969 NASCAR International Stock Car Racing Rule Book NASCAR Grand National Championship Circuit Section 20-23 -- Carburetor

a. Carburetor must be available production model in manufacturer's line. No external alterations permitted.

(1) Rocker arm hemispherical combustion chamber engines restricted to one four-barrel carburetor having 1 11/16 inch throttle.

(2) Overhead cam type engines restricted to one four-barrel carburetor having 1 11/16 inch throttle bore.

(3) Wedge type engines restricted to one four-barrel carburetor having 1 11/16 inch throttle bore.

(4) Engines with staggered valve design restricted to one four-barrel carburetor having 1 11/16 inch throttle bore.

(5) Intake manifold unrestricted within manufacturers line, readily available to participants. Materials optional.

b. Fuel injection or superchargers not permitted.

c. Jets may be any size.

d. Wedges permitted.

e. Heat risers may be blocked.

f. Any NASCAR approved gasoline filters may be used. This applies to all late model divisions as well as speed trial and record attempts.