That's right, in 1959 Buick juggled the names of their models and the top-of-the-line Roadmaster became the Buick Electra 225.
The "Electra" name came from Electra Waggoner Biggs, Texas socialite, sculptor, and land baroness, who was the sister-in-law of then-GM president Harlowe H. Curtice. The "225" appellation was the overall length in inches of the big 1959 Buick, from gleaming chrome snout to rakishly finned tail.
The Arctic White 1964 Electra 225 hardtop coupe in these photos represents the final iteration of the second generation of the famed "Deuce and a Quarter", which spanned the '61-'64 model years.
The base motor was the 401 cubic inch Buick "Nailhead" V-8 with a four-barrel carburetor, rated at 325 SAE gross horsepower. (Buick’s overhead valve V-8 was dubbed the “Nailhead” by period hot-rodders because of the small valves relative to the long stems, reminiscent of nails.) The only transmission available for '64 was the 3-speed GM Turbo-Hydramatic 400, which Buick sold under the "Super Turbine" moniker.
Buyers could opt for the bigger version of the Nailhead, in 425 cubic inch guise. The 425 was offered in regular format, rated at 340 bhp with a 10.25:1 compression ratio and a single Carter 4bbl carb, or a "Power Pack" version with a pair of Carter 4bbls and dual exhaust, rated at 360 bhp.
The car in the picture doesn't have dual pipes, so it's either a 401 or the regular 425.
An interesting bit of trivia regarding the 401 cid Buick Nailhead: The United States Air Force used a special starter cart with a pair of the big V-8s to spin up the Pratt & Whitney J58 turbojets on the SR-71 Blackbird. (Later versions of the cart used a brace of Chevy 454's.)
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