1965 NASCAR International Rule Book Specifications NASCAR Grand National Championship Circuit Section 20-1 -- Competing Models

a. NASCAR Grand National Circuit races are open to steel-bodied 1963, 1964 and 1965 models of American-made passenger car production sedans with a minimum wheelbase of 116 inches, classified by NASCAR as Grand National cars, except that cars with a minimum wheelbase of 119 inches only will be allowed to compete at Atlanta International Raceway, Charlotte Motor Speedway, Darlington International Raceway, and Daytona International Speedway.

b. 1963-64 models -- All approved makes and models of 1963 and 1964 cars will be allowed to compete under rules and regulations governing the 1965 season, provided they are re-constructed to conform with the specifications covering the 1965 season as detailed in this Rule Book for 1965 competitions.

c. 1965 automobiles -- Eligibility requirements as follows:

c-1. Permissible engines must be production engines similar in design to the popular normal production engine and readily available to the public through regular trade channels at a dealer's catalogued list price.

c-2. All engines in 1965 must have original production cylinder heads, blocks and intake manifolds. Internal modifications to cylinder heads, blocks and intake manifolds are permitted provided the firing order is not changed, and the total displacement does not exceed 428 cubic inches. No roller tappets are permitted.

Cubic inch displacement limit for Cadillac, Lincoln Continental or Imperial is 429 cubic inches.

c-3. All manufacturers' advertising must mention that equipment meets NASCAR Grand National specifications. Failure to include this reference may mean the loss of manufacturers' point ratings.

d. Should 1966 models be available during 1965 championship season, cars will have to be approved by NASCAR.

e. No changes from standard production automobiles or component parts will be permitted except as specified in the following specifications or by written authorization from NASCAR International Headquarters.