1966 NASCAR International Rule Book Specifications NASCAR Grand National Championship Circuit Section 20-1 -- Competing Models

a. NASCAR Grand National races are open to steel bodied 1964, 1965, 1966 models of American-made passenger car production sedans, classified as follows: Standard, Intermediate, Compact, Sports and Grand Touring.

Category 1--Standard or larger size cars.

Limited to cars with a minimum of 119-inch wheelbase, with a maximum engine size of 430 cubic inches piston displacement.

The following 1966 cars have been classified in Category 1, with additional model names to be added:

BUICK--LaSabre, Wildcat, Electra, Riviera

CADILLAC--Calais, de Ville, Fleetwood Special Sedan, Fleetwood Limousine

CHEVROLET--Chevrolet (Impala)

CHRYSLER--Newport, 300, New Yorker

DODGE--Polara, Monaco

FORD--Ford (Galaxie, Custom)

IMPERIAL--Crown, LeBaron

LINCOLN CONTINENTAL

MERCURY--Mercury

OLDSMOBILE--Jetstar 88, Dynamic 88, Delta 88, Ninety-Eight, Starfire, Toronado

PLYMOUTH--Fury

PONTIAC--Star Chief, Bonneville, Grand Prix, Catalina

Category 2--Intermediate size cars.

Limited to cars with a minimum of 115-inch wheelbase, and less than 119-inch wheel base, with a maximum engine size of 405 cubic inches piston displacement.

The following 1966 cars have been classified in Category 2, with additional model names to be added:

BUICK--Special, Skylark

CHEVROLET--Chevelle

DODGE--Coronet, Charger

FORD--Fairlane, Thunderbird

MERCURY--Comet

OLDSMOBILE--F-85

PLYMOUTH--Belvedere

PONTIAC--Tempest, GTO

RAMBLER--Ambassador

NOTE: Category 2 cars may run in competition with Category 1 cars if specified on the entry blank. On speedways more than a mile in length, Category 2 cars may use any production displacement not to exceed 405 cubic inches as compared to the maximum engien size of 430 cubic inches allowed for Category 1 cars. On tracks of one mile and less and road courses, both Category 1 and Category 2 cars may use any production displacement not to exceed 430 cubic inches. All cars in any event must weigh at least 9.36 pounds per cubic inch as spelled out in 1-B.)

Category 3--Compact cars.

Limited to cars with a wheelbase of less than 115 inches, with a maximum engine size of 335 cubic inches piston displacement.

Category 4--Sports cars.

Category 5--Grand Touring cars.

(The specifications for the Grand National Division, in essentially the same form as listed here, have been accepted by the Automobile Competition Club of the United States -- FIA and by the FIA for inclusion in the Appendix J. They will be listed in Category 5B of the special touring sedan section.)

b. Minimum weight for all classes:

9.36 lbs. per cubic inch of piston displacement, with gas, oil and water, ready for racing without driver.

c. All new production models and production engines introduced not later than Dec. 31st of each year will be classified eligible for competition in the following year. New models or engines introduced after Dec. 31st will not be eligible for competition until 90 days after introduction. The 90-day period must expire no later than the first day of official qualifying for the initial event in which the equipment is entered.

d. Engine eligibility.

No overhead cam engines permitted unless approved by NASCAR.

Volume production engines only (no limited production engines) and the volume production classification will be determined by spot checks of the various assembly lines when such checks are deemed necessary.

Engine assemblies, exclusive of carburetor and exhaust manifolds, must list in the $1,000.00 price range, exact limit to be announced following model introductions.

e. No changes from standard production automobiles or component parts will be permitted, except as specified in the following specifications.