Leading the way in the 1960s multi-cylinder race was Packard, which in 1955 was desperately seeking to recover some of its squandered past glory. The idea was a V-12 derived from its just-announced V-8.
According to former product planner Richard Stout, this would have been machined on the V-8 line, the longer block being moved "halfway down" to bore the extra cylinders.
Since the V-8 block was a 90-degree "Y," 30 degrees out of phase for the "in-step" firing desirable in a V-12, each rod throw would be staggered 30 degrees to compensate. Buick would use this same "split-throw" principle for its 90-degree V-6 in the early 1960s.
With 480 cubic inches and all the horsepower that implied, Packard's postwar V-12 would have been a mighty work indeed. But as Dick Stout remembered: "It was strictly grandstand stuff. . . . Tooling was guesstimated in the $750,000 area -- modest for such a spectacular result. . . . But in the end the money just wasn't there."
In fact, Studebaker-Packard then faced imminent bankruptcy and so abandoned luxury Packards after 1956, substituting medium-priced Studebaker-based cars through the marque's sad demise in 1958.
A few years later, Cadillac Division took its own stab at modern multi-cylinder power. The attempts followed two paths: a fairly crude, "bolted together" V-16 composed of two V-8s, and an exotic all-new V-12 with single overhead camshaft.
The contemplated V-16 probably had nothing to do with Cadillac's own V-8. By 1960, the division's milestone 331 V-8 of 1949 had swelled to nearly 400 cid, which would have made a twin-block sixteen simply gargantuan.
A more likely choice was Chevrolet's 283, which would have doubled-up to 566 cid -- big, but not impossible. According to former GM Design Director Chuck Jordan, who then headed Cadillac Styling and worked on that side of the V-16 revival, this engine was more conjecture than concrete proposal.
"We were working with Engineering Staff to put two V-8s together," he later recalled. "It was kind of a homemade way to do it, but it was just to project an image we wanted to get across to [division management] at the time. Nothing serious was ever developed engineering-wise."
More intriguing was the clean-slate V-12 being prepared at the same time. Jordan remembered this as "a very sophisticated powerplant, and quite beautiful. I'm sure it was designed from scratch as an overhead-cam engine -- a very exciting piece of machinery to see."
Also a 90-degree unit, it was designed for instep firing à la Packard's stillborn V-12. Aside from that and sohc heads, technical details remain obscure.
It's unclear whether the clean-slate V-12 or the crude V-16 were ever seriously considered for production, but there's no doubt that development stopped at the prototype stage. Still, Chuck Jordan and his colleagues came up with a remarkable group of design studies for a new multi-cylinder Cadillac.
To learn more about these multi-cylinder ideas, check out the next section.