The Chevrolet Impala was launched as a Sport Coupe and Convertible variant of the 1958 Bel Air line, and named for an African antelope. Chevrolet had completely redesigned its product lineup for 1958 and the Impala had a number of unique features to separate it from the standard Bel Air. The three 1958 nameplates were Del Ray (6 models), Biscayne (4 models) and Bel Air (5 models) plus the two top price Impalas.

The Chevrolet Impala would become its own two- and four-door model line in 1959 and was the best-selling model in the U.S. in 1960. It held that position for 10 years and by 1966, 13 million Impalas had been sold, including a one-time total of one million Impalas in 1965.

Chevrolet sold 1,255,935 cars for the calendar year 1958, against 1,038,560 for Ford, taking the number one spot. Of those sales, 125,480 were 1958 Impala Sport Coupes and 55,989 were Convertibles – about 15 percent of the total. Base price for the Coupe was $2,586, and for the Convertible it was $2,724.

All 1958 Chevrolets were longer, lower and wider than 1957 and rode on a new X-frame, with coil springs front and rear. Designer Bill Mitchell had replaced the fins and simple straight lines of the ’57 models with baroque curves. Incidental aluminum brightwork was scattered everywhere. All models had full-width mesh grilles and four headlights. Station wagons had single taillights on each side and other models had twin taillights, while the Impalas had signature triple taillights.

Impalas also had script and crossed flags in front of the side styling coves, ribbed rocker panels and faux air intakes ahead of the rear wheels. The name was repeated on the dash and the rear radio speaker. The sports wheel had a deep dish center and there were special “flipper” hubcaps. The center section on the roof of the Sport Coupe was raised and swooped towards a dummy air scoop at the rear. Impala offered the only convertible in the 1958 lineup.

Base engines were a 145 bhp, 235 cis six and a 185 bhp, 283 cid V-8, but options included the 230 bhp four-barrel Super Turbo-Fire V-8 ($27) and two dual four-barrel setups. One offered 245 bhp for $150 and the other 270 bhp for $183. The big-block 348 cid engine was available as a 250 bhp Turbo-Thrust V-8 ($59), and two Super Turbo-Thrust 348 V-8s. Both had three two-barrel carburetors but the first shared the 9.5:1 compression ratio of the other engines and generated 280 bhp ($70). The “M” maximum performance Special Turbo-Thrust 348 V-8 had an 11:1 compression ratio and solid lifters, and was good for 315 bhp. A Rochester mechanical fuel-injected small-block 283 V-8 engine generated 290 bhp but cost a hefty $484.

Air suspension was offered for $124, but proved troublesome and was eventually discontinued, with most cars converted to conventional springs. The base gearbox was a three-speed manual, and an overdrive could be added for $80. A four-speed could be added for $188. There was also a two-speed automatic Power Glide and a Turbo-Glide four-speed automatic cost $231. Air conditioning cost $468, power windows $102, push button radio $84, power brakes $38, power steering $70, dual exhaust $16, oil bath air filter for $9 and oil filter $5.

Chevrolet offered 15 new solid colors for 1958, and 15 two-tone combinations with quite a few metallic colors and about 40 different two-tone cloth and vinyl interior colors. Here are the external colors and codes, where available: Aegean Aqua, Arctic White, Inca Silver, Onyx Black (900), Glen Green (903), Forest Green (905), Cashmere Blue (910), Fathom Blue (912), Tropic Turquoise (914), Aegean Turquoise (916), Anniversary Gold (918), Sierra Gold (920), Rio Red, (923), Colonial Cream (925), Silver Blue (930), Clay Coral (932), Snowcrest White (936), Regal Turquoise (904A), Signet Red (906A), Panama Yellow (508A), Honey Beige (938A), and Sierra Gold (920).

Two-tone colors included Onyx Black / Arctic White, Arctic White / Glen Green, Forrest Green / Glen Green, Arctic White / Cashmere Blue, Fathom Blue / Cashmere Blue, Arctic White / Tropic Turquoise, Aegean Turquoise / Arctic White, Aegean Turquoise / Tropic Turquoise, Arctic White / Sierra Gold, Rio Red / Arctic White, Colonial Cream / Arctic White, Cay Coral / Arctic White, Silver Blue / Snowcrest White, and Anniversary Gold / Honey Beige.