As we covered in our last installment, the Cadillac Eldorado was “all-new” for 1963 as GM repositioned its flailing flagship convertible. While the rest of the lineup existed as a refresh of the 1961-1962 generation, Eldorado was set apart. Not that it looked different to the rest of the model range, as it received the same visual updates. Eldorado was considered new, special, because of its change in construction: It ascended the ranks in 1963 to the Fleetwood assembly line. And there were a few new details under the skin to draw in the consumer.
Remaining steadfast was the C-body platform that underpinned all standard sized Cadillac models since the first Sixty-Two of 1940. Eldorado’s wheelbase of 129.5 inches carried over into 1963, as chassis rolled down the Fleetwood line alongside (or perhaps near to) the luxurious Sixty Special and Seventy-Five series cars. Overall length increased by an inch over 1962, to 223 inches.
Like the similar but less exclusive Sixty-Two convertible, Eldorado’s width decreased from 79.9 inches in 1962 to 79.5” in 1963. Due to their extra equipment, Eldorados weighed between 4,800 and 5,000 pounds, roughly 100 more than a Sixty-Two convertible equivalent. All Cadillacs of 1963 were powered by the same overhead valve 390 (6.4L) V8. However, the 1963’s 390 wasn’t the same as the 390 of 1959 origins.
The original 390 was created when Cadillac added a longer stroke (3 and ⅞”) to the 365 V8 of 1956, which boosted power to 325 horses. The power figure jumped to 345 horses when the engine was fitted with the upsell Tri-Power triple carb. This version of the engine existed only between 1959 and 1962. Though it carried the same displacement, the 390 series engine of 1963 was a complete rework. Cadillac’s engine line was modernized that year with new tooling, and the engine itself was different to the previous OHV and its origins in 1949.
The engine’s general architecture and layout were carried over from the prior V8, but the overall package was an inch lower, four inches narrower, and 1 and ¼ inch shorter. There were shorter connecting rods in the new engine, and a brand new housing. Made out of aluminum, the housing was the mounting point for the power steering pump, distributor, and water pump.
Further advancements came in the form of a new-fangled alternator to replace the engine’s previous generator. And the crankshaft was revised to make it stronger and lighter. Bore and stroke were the same 4” x 3.875” of the previous engine. The compression ratio was 10.5:1. A four-barrel carburetor was standard, and the only configuration available.
These changes amounted to a power plant that was more modern, more compact, and 52 pounds lighter than its predecessor, but with the same 390 cubic inch displacement. Power was standardized at 325 horses and 430 lb-ft of torque. The new 390 series OHV engine proved a very short-lived mill, and existed only from 1963 to 1964 before it was replaced by ever-larger displacement variations. Domestic automobiles headed toward the Seventies with an optimistic eye on huge displacement and torque figures. Surely that would never change!
In other engineering news, Cadillac heralded a “true-center drive line.” The company promised with modern design and precision assembly of the engine and transmission that noise, vibration, and harshness or “driving impulses” were isolated or canceled. Worth noting, the transmission itself was a carry-over: the same four-speed Hydra-Matic used for years at GM. The Hydra-Matic reached its end of life that year (1940-1963) and was replaced by the Turbo-Hydramatic (TH400) in 1964.
Cadillac also touted an exclusive refinement feature in its separate front and rear power brake systems, and the separate tertiary auxiliary parking brake. Brakes (all drums) were reworked with fins for better cooling, and better longevity. Brakes were also self-adjusting for the sake of lower maintenance.
Standard on all Cadillac models in 1963 were power steering, power brakes, the four-speed automatic, and a heater and defroster. Interestingly for the skinflint Cadillac customer (strange!) every single Cadillac in 1963 could be ordered without a heater and defroster. One wonders if any cars were ordered in ‘63 with no HVAC at all.
Another oddity comes into view for this particular model year: The DeVille Park Avenue sedan with its stumpy 215-inch length required owners to suffer more than just the indignity of a Cadillac that was smaller than it could’ve been. The reduced space all taken from the rear deck meant the fuel tank shrank. At 21 gallons, cruising range was significantly reduced over the 26-gallon capacity of other Cadillacs.
More standard features were added to all Cadillac models, with additional niceties made standard for elite models like Sixty Special and Eldorado. Things like cigarette lighters, cornering and reversing lights, armrests, a rearview mirror with tint (Fleetwood models only), and sun visors were all standard. Wheel covers, a window washer, and even a trunk light that was automatic were also standard.
Beyond those, customers could go wild with the Eldorado’s interior should they be so inclined. Cadillac offered a multitude of luxury options the Sixty-Two convertible (or “Cadillac Convertible”) buyer could only dream of. Bucket seats in a choice of leather, wool, or nylon upholstery, different wood veneer options for the dash and backs of seats, and a bevy of additional smaller options. There were a total of 143 interior options for the Eldorado customer to review in 1963, a record at GM
And prospective buyers knew these options were fitted by the craftsmen of the Fleetwood line, who would imbue the entire car with an air of higher quality. That’s assuming they liked the Eldorado’s more subdued appearance and its general lack of trim. We’ll take a look at the exterior revisions of 1963 in our next entry.
[Images: GM, dealer]
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