The carburetor must be correct for the year, make, and horsepower claimed. Jetting and metering changes are permitted. THE CHOKE ASSEMBLY MUST BE IN PLACE AND FUNCTIONAL! Mechanical secondary carbs cannot be substituted if vacuum operated units were original to the car. Mechanical fuel pumps must be retained. Electric fuel pumps are NOT allowed. No fuel pressure gauges are allowed anywhere along the fuel system. Factory fuel lines are required and must be correct size. No rubber lines allowed unless originally equipped as such. No fuel cells are allowed
Cast-iron exhaust manifolds are mandatory and must be correct for the year, model, and horsepower claimed. Internal modifications to the exhaust manifolds are NOT allowed. Under no circumstances will headers be allowed, including those cars that came with headers delivered in the trunk. The exhaust system may be upgraded to a maximum of 2.5-inch head and tail pipes. Pipes must be routed as they were originally for the year, make, model, and engine combination. Mufflers must be stock looking in design, that is, oval in shape. No glasspacks or straight pipes allowed unless installed as original equipment. Maximum muffler inlet and outlet size is 2.5 inches. X & H pipes allowed.