Photos: RM Auctions

In 1954, Corvette production moved to a newly renovated facility in St. Louis, where 10,000 Corvettes were planned to be built every year. Actual production had begun in December of 1953, however the full model year’s tally only made it to 3,640 units. Nearly one third remained unsold by December of 1954.

Mid year production saw a camshaft change that increased horsepower to 155 in the 235 cid six-cylinder engine, all Corvettes retained the Powerglide automatic transmission. Three new colors – Pennant Blue, Sportsman Red and Black – were added to the standard Polo White. A beige interior was also offered, but none of this was able to enchant the buying public.

GM styling chief Harley Earl commissioned approximately 20 plastic bubble canopy tops for the 1954 Corvette, most of which went to special customers and dealers, and so, while 1954 Corvettes are highly prized by collectors, the so-called “Bubble-Top” version is the rarest of the rare.

As a result of a visit to Selfridge Air Force Base, several years prior, Earl had become fascinated with styling themes based on the jet aircraft. The 1948 Cadillac had sprouted tail fins as a result and the similarity of these Bubble Tops to an aircraft canopy is undeniable.

The project began in 1953, as early Corvette owners cited limited headroom and visibility as deficiencies in the newly designed car. Eugene Kettering, chief engineer of GM’s Electro-Motive Division, owned one of the early 1954 models and could appreciate the feedback. With Earl’s blessing, Kettering contacted William Chaffee from a company called Model Builders, in Chicago, IL.

The recently founded company had developed an expertise in plastics fabrication, a relatively new commercial skill at te time. Acrylic plastic (a.k.a. Plexiglas, Perspex) had only been available in sheet form since 1936 and had seen much wartime use. Chaffee’s company built a number of the Bubble Tops, one of which ended up on Kettering’s car. Sources vary on the number of tops actually built, ranging from 20 to 25.

The tops, reportedly, were not GM’s finest piece of engineering that year. Airflow and water sealing were minimal, while its ability as a passive solar collector was impressive. Lessons would be learned, however, as a similar top shown on the 1961 Mako Shark was largely covered with vaporized aluminum to increase protection from the sun.

Two other tops, similar to the 1954 Model Builders version, were later offered in the aftermarket by Plasticon of El Monte California, and Scottop, also from the Golden State.

The 1954 “Bubble Top” Corvette shown here is part of the offering at the upcoming RM Auctions’ Automobiles of Arizona, January 20-21, 2011, at the Arizona Biltmore Resort & Spa in Phoenix, AZ. More information is available from the event web site.