In 1958, the Impala was introduced as a top of the line Bel Air hardtop and convertible. The 1958 Bel Air Impala was designed be structurally different from Chevrolet’s more economically-priced models. Across the board, the 1958 models were longer, lower, and wider than those of previous years. Gone were the tailfins of the 1957 models, replaced by rear quarter panels that feature what many call a a more sculptured look.
A 283 cubic-inch engine was available in two carbureted versions, or with the Ram Jet fuel injection.
This year marks the appearance of the X-frame, as the perimeter-style frame was abandoned. According to Chevrolet, this new frame design offered increased torsional rigidity, and allowed for a lower passenger compartment. It was soon learned that the X-frame was not as good at protecting the passengers during a side impact crash as a traditional perimeter frame. A coil spring suspension as opposed to a leaf spring-style suspension. A technologically-advanced (for the times) an air ride suspensions system was available.
The Impala was a large car, so it is surprising that anything other than a V8 engine would be available under the hood. If so inclined, you could however get your new Impala with a 235 cubic-inch inline Blue-Flame six cylinder. Delivering 145 horsepower, we’re certain it was never used as a getaway vehicle for nefarious activities. Stepping up to the base V8 engine, buyers got a 283 cubic-inch engine with either a two or a four-barrel carburetor shelling out 185 or 230 horsepower respectively.
There was one more 283 cubic-inch engine available, but it was not a popular option. If you ordered your small-block with the Ram Jet fuel injection, you could actually see 250 horsepower from your small-block. New for this year was a “big-block,” referred to as a W-series engine. With a four-barrel carburetor, the base Turbo-Thrust produced 250 horsepower, while a Super Turbo-Thrust featuring three, two-barrel carburetors upped the power output to 280 horsepower. A Special Turbo-Thrust was also available with a single, large four-barrel carburetor, and punished the rear tires with 305 Horsepower. Finally, if you didn’t mind solid lifters and the trio of two-barrel carburetors, you were the right person to get the “Special Super Turbo-Thrust” engine that delivered 315 horsepower.
A total of 55,989 Impala convertibles and 125,480 coupes were built, representing 15 percent of Chevrolet’s total production. The 1958 Bel Air Impala helped Chevrolet regain the number one production spot during this recession year.