As the 1962 drag season drew to a close, it was obvious that Pontiac’s position at the top of the Super Stock hierarchy was weakening. Ford, Chrysler and Chevrolet were gaining on the Chiefs with bigger engines and an ever-increasing supply of special parts, including weight-saving aluminum components and body panels. Pontiac engineers knew they had to have a lighter, more powerful car for 1963, and it came in the form of a special Catalina bearing some serious modifications. First the chassis was altered by cutting the inside section away from the boxed rails, leaving a U-shaped section. Then approximately 120 holes were drilled in the sides of the frame rails, removing as much material as possible while maintaining a semblance of structural integrity, resulting in the “Swiss Cheese” moniker that remains today.
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