There are some who would argue that 1967, not 1969 or 1970, was the peak year for automotive performance during the muscle car era. Whether or not that is true, one thing is for certain; by 1967 high performance in a full-sized car was quickly becoming an outdated concept.

Every motor vehicle corporation had lessened their restrictions on large engine displacements in smaller vehicles. The result was mega-horsepower engines finding their way into small, lightweight cars that could easily dispatch lesser competition. There were few buyers who found the idea of a large frame car packed with a high-performance engine appealing anymore.

Nevertheless, for those true full-size die-hards out there, Chevrolet came through for them with a new high performance package of options to supplement the standard Impala Super Sport; the SS427.

This new option was only available on the Impala Super Sport sport coupe and convertible models, which were in their last year as separate models in the Impala lineup. The standard Impala Super Sport no longer carried the swagger it had enjoyed in years past, now featuring an increased emphasis on luxury and good looks instead of performance. Essentially, the Impala SS models boasted nothing more than a trim package and the 1967 Impala SS could be had even with six-cylinder engines. That certainly didn't appeal to anyone who wanted some "bang" for their dollars. So, in an attempt to restore the sporty, performance image to the Impala Super Sport, Chevrolet introduced the SS427.

Chevrolet's Regular Production Option (RPO) code for this newest Super Sport was Z-24 and it finally gave big Chevrolet enthusiasts a Super Sport to get excited about again. A 385 horsepower 427 cubic inch V-8 engine, special domed hood, heavy duty suspension and front stabilizer bar and "SS427" emblems in several locations certainly seemed able to satisfy the appetites of even the most demanding customers. But interest in the full-sized Chevrolet as a performance oriented vehicle was waning. The extra cost and added weight of a full framed car just wasn't a viable option for those customers seeking to buy a high performance automobile. With only 2,124 of these special Impalas being produced, it was clear to Chevrolet executives what direction Impala was headed as the decade drew near to a close.