One of Chevrolet’s most iconic models, the Impala goes back to 1956 when the company used the name on a concept car with Corvette-like styling cues. The badge was then assigned to a production model in 1958 and remained in showrooms until 1985. The Impala returned from 1994 to 1996 and from 2000 to 2020.Come 2023 and the late 1950s and early 1960s Impalas are the most desirable iterations of the full-size car. The SS models are particularly sought-after, especially if they pack big-block power under the hood. But it’s the first-year version that stands out as the rarest.
A top-of-the-line trim level of the Bel Air two-door hardtop and convertible, the 1958 Impala moved almost 181,500 units. Not exactly rare, right? Well, the total production figure may be high, but it’s nowhere near as high as the model years that followed. Because the Impala ended up selling more than one million examples per year in the 1960s.
But the red Impala you see here is not a run-of-the-mill 1958. The convertible layout narrows the production number to 55,989 units. And the drivetrain combo that makes it truly rare. Chevrolet offered the Impala with a selection of three engines that year. The base model was obviously fitted with the 235-cubic-inch (3.9-liter) “Blue Flame” inline-six. Rated at 145 horsepower, it wasn’t exactly enticing.
However, customers also had access to the 283-cubic-inch (4.6-liter) V8, which generated from 170 to 230 horsepower depending on the carburetor and transmission setup. A fuel-injected version of the same mill came with 250 horsepower on tap. But the engine lineup also included the then-new 348-cubic-inch (5.7-liter) W-series big-block V8. This Impala is equipped with the latter.
Here’s the thing, though: it wasn’t ordered with the regular 348 “Turbo-Thrust” rated at 250 horsepower. The original owner went with the 3×2-barrel variant. Also known as the “Super Turbo-Thrust” or the “Tri-Power,” this mill sent 280 horses to the rear wheels when new. There are no records of how many 1958 Impalas got the 348 “Tri-Power,” but you won’t see too many nowadays, especially in tip-top condition.
Then there’s the four-speed manual, which is rarer than hen’s teeth on 1958 Impalas. How so? Well, Chevrolet offered the full-size with three gearboxes that year, including a three-speed manual and a couple of automatics (two-speed Powerglide and three-speed Turboglide). The four-speed, introduced on the Corvette in 1957, didn’t make it into full-size cars as a factory option until 1959.
However, some 1958 Impalas got the manual as a dealer-installed option, which became available in early 1958 as RPO 685. Again, there’s no info on how many were fitted before delivery, but we’re probably looking at one of only a few examples. If we also factor in the power steering, power brakes, red-on-red finish, and the white soft top, this 1958 Impala is likely a one-of-one gem.
But regardless of its status among the first-year Impala lineup, this convertible is a show-stopper. It is perfect from every angle and sports a continental kit. I don’t know about you, but I love these bumper extensions that move the spare wheel outside the trunk. This one was added by the owner in the 2000s, but it’s a period-correct unit. Moreover, it turns out this Impala is a low-mileage survivor with only 17,000 miles (27,359 km) on the odo. It really doesn’t get better than this!