CTCI Authenticity Chairman
Photo # 1 shows an original 1957 air cleaner base. The purpose of the three raised areas in the lower dome is to prevent the chrome plated top cover from being sucked down during acceleration. Some of the reproduction air cleaners do not have these raised areas which allows the chrome cover to shut off or restrict air supply during other than normal acceleration such as on ramp or passing acceleration. This has happened a few time with one of our club members. The vehicle continued to accelerate, the engine had to be shut down by turning the ignition key off. The volume of air required by the carburetor for acceleration caused the throttle plates to stick open and the car would not de-accelerate until the ignition was shut off. The cause for this condition was discovered by Bill Mann a very experience Thunderbird mechanic, CTCI and Santa Clara Valley Thunderbird Club member.
Photo # 2 shows one solution to prevent the problem that could occur on the reproduction air cleaner assemblies. Install a 1/4 inch nut and large flat washer on the air cleaner stud. Adjust the nut and washer so the chrome top will seal against the air filter element and high enough to restrict down movement of the chrome cover during acceleration. While installing the nut & washer use caution not to drop the nut down the throat of the carburetor.