07/12/2025
1958 Chevy Impala Convertible
Triple tail lights on each side set the inaugural Impala apart from other 1958 Chevrolets, which used double units (or single lamps on wagons). The convertible featured distinct bodywork from the A-pillar rearward, with a slightly shorter greenhouse and longer rear deck than standard Bel Airs to emphasize its lower, sportier profile.
Chevrolet positioned the Impala as the range-topping full-size trim level, available only in Sport Coupe and convertible configurations during its debut season, with production totaling 55,989 convertibles and 125,480 Sport Coupes.
The 348 cubic inch W-series V8 arrived for 1958 as Chevrolet's first big-block engine, originally developed for medium-duty truck duty and then adapted for passenger car use. Its unusual designation and appearance came from the scalloped shape of the rocker covers and the distinctive W-shaped combustion chamber formed in the block.
The Super Turbo-Thrust version employed Tri-Power induction through three Rochester two-barrel carburetors, typically rated at 280 horsepower at 4,800 rpm in 1958 full-size applications. Under normal operation only the center carburetor fed the engine, with a vacuum-operated linkage bringing in the front and rear units as the throttle opened past a preset point under heavy load.
The Impala's tritone upholstery pattern and two-tone steering wheel were exclusive to the model, distinguishing it from lesser Chevrolets in both appearance and appointments, and reinforcing its image as Chevrolet’s flagship for 1958.