Nearly from the birth of the automobile, manufacturers have strived to make cars better and more affordable. While DKW (now Audi) is credited by many for producing the first mass-produced unibody car in 1928, other manufacturers had previously offered low production-number unibody cars years earlier. Chrysler toyed with unibody car design in the 1930s with their Chrysler and DeSoto airflow models, but it was Nash who offered the first full production line of unibody cars in 1941. The benefits of the unibody design were reduced weight, lowered vehicle stance, better fuel economy, reduced manufacturing expense and smoother ride. But for the serious performance enthusiast, the unibody design flexed too much to give consistent driver feedback and road control.
By the early sixties, most of Chrysler’s cars had adopted the unibody platform, while GM and Ford used it primarily on their smaller sized and economy cars. But as the horsepower race of the sixties was in full force, one of the weaknesses of the unibody design became apparent. The shaking, twisting, and flexing of the body on high-horsepower cars soon led to cracked glass, body alignment issues, cracked paint, and wrinkles in sheet metal. As unibody cars aged and the numerous spot welds holding the panels together had been stressed by performance and corrosion issues, the problems only became worse. Since rebuilding a car’s entire structure from scratch is impractical, the performance industry responded by creating subframe connectors.
Subframe connectors serve to connect the unibody car’s front and rear suspension together to add rigidity to the cars body. The added stiffness helps eliminate body twist and flexing in performance driving and increases road stability in street driving. We join Mark and Gary Simpson in the shop as they take on the task of stiffening up a 1967 Ford Mustang with a set of subframe connectors. Gary discusses the difference between bolt-on and weld-in subframe connectors as he demonstrates how to install them and have our pet pony project handling better than ever.