A Look At The Three Corvette Assembly Plants

Building America’s Sports Car

Jim Smart – Writer

In 1953, who would have believed that an American automaker—known more for great styling rather than road-going, canyon-cutting performance—would give the world an exciting two-seat sports car. American automakers in the post war period introduced fresh and exciting models erected on new underpinnings with updated sheetmetal and creature comforts. In the early 1950s, Chevrolet had its eye on building a fierce competitor to European sports cars. European sports cars were enjoying a healthy market share in the United States and GM wanted a piece of the action.

The Corvette was named for those small, fast-moving naval vessels employed by the British Navy more than a century ago. It seemed a suitable name for Chevrolet’s flagship sports car when it was debuted early in January 1953 at the Motorama shows in New York City and Detroit. The Corvette was an exciting and welcome concept car that excited a lot of potential buyers who wanted to know how to get one. GM’s marketing and product planning people went back to their jobs conceiving America’s sports car.

When the first mass production Corvette was bucked and assembled at GM’s Flint, Michigan, assembly plant on June 30, 1953, it launched not only a legendary flagship product line for GM, but also a passionate movement that has lasted nearly seven decades. (The first two production Corvettes were assembled in a temporary facility in the customer delivery garage; reported to be an old building on Van Slyke Ave. The ’54 and later cars were assembled in the renovated St. Louis facility.) The Corvette was born as a fiberglass body on a steel frame sports car designed by legendary stylist Harley J. Earl, who birthed the hot-selling Buick LaSalle in the late 1920s. The LaSalle tanked badly during the Great Depression. However, that didn’t deter GM. Earl penciled out the 1950 Buick LeSabre, which performed very well in the marketplace. Chevrolet then looked to Earl to come up with a sporty two-seat design for its Motorama display. Although it has been widely written Zora Arkus-Duntov designed the Corvette, it really was Earl who birthed America’s sports car in the first place. Duntov would become very influential in its continuing development a short time later.

Chevrolet’s first attempt at what would become Corvette was code named EX-122. Mass production began in earnest with 300 Polo White Corvette roadsters with red interiors, which were produced during the summer and fall of 1953, making these coveted rides the only Corvettes the Flint assembly plant would ever produce. Beneath its fiberglass epidermis, the Corvette wasn’t much to write home about. It was built on the same basic chassis as other Chevrolet sedans of the era, which didn’t make it competitive with its European counterparts. The Corvette was powered by the 235ci “Blue Flame” six, which certainly wasn’t wowing anyone despite its side-draft induction system. However, it was all Chevrolet had in 1953. The 265ci small-block V-8 wouldn’t be available for two more years.

Planned production at Flint was 50 units a day, which called for a handful of assembly skids and workers to meet the demand. Because so few Corvettes were produced in 1953, only a select few—celebrities, politicians and GM executives—were able to get their hands on one. This was an intentional strategy staged by GM management to spur demand. That plan backfired. Demand didn’t meet expectations because Corvette had a long way to go in terms of refinement and buyers quickly grew tired of waiting.

Although St. Louis was always the planned assembly plant for the Corvette, St. Louis was never going to be ready in time to build the Corvette on a mass scale with the few short months of advanced notice it had been given by GM management. It was going to take months to tool up for the Corvette. GM had to come up with a short-term solution on how to build 300 Corvettes before the end of the 1953 model year.

There were two assembly lines at Flint for the Corvette: body and chassis. Capacity was a modest six units at a time. The bodies were built and assembled on one line while painted frames were assembled on the other. Once Flint had rolling chassis ready for completion, fiberglass bodies were lowered onto them. Tony Kleiber, a Flint plant worker, drove the first Corvette, E53F001001, off the line on June 30, 1953, while Plant Manager F.J. Fessenden and General Manager R.G. Ford looked on and posed for the ceremonial drive-off. This was one of those rare moments where the symbolic Job 1 was actually serial number 001.

Because Corvettes were of fiberglass construction, this made them more time consuming to produce. When the fiberglass bodies came out of the molds the real work was only beginning. The seams and joints had to be filled and sanded. The environment was crude with resin and fiber dust in the air and virtually no lung protection for plant workers. Corvette body parts were produced both in-house and by outside suppliers like the Molded Fiber Glass Company. GM used the “bag” fiberglass process for Corvette bodies where a plastic vinyl sheet was applied over the fiberglass to reduce work time and to provide a more user-friendly surface with less prep time.

Corvette builds began with the fiberglass platform fitted with reinforcements designed to make it stiffer and to safely support occupants. Before the platform could be mated to the body shell, some 200 mounting holes had to be drilled into the platform. To ensure accuracy, a special drilling fixture had to be mated to the fiberglass platform. Once the platform was ready for body join, it was mounted on a rolling assembly skid that followed tracks down the line.

Because fiberglass was leading-edge technology in 1953, Flint assembly had more than its share of growing pains. Air bubbles in the fiberglass surfaced during the paint drying process in hot 300-degree ovens. That meant repair and repaint time plant management didn’t plan for. Especially remarkable was how light these Corvette bodies were compared to steel; just 411 pounds, about two-thirds what a steel body would have weighed. However, it would have been easier to produce the Corvette as a steel body. GM wanted leading-edge technology, hence the Corvette’s fiberglass construction.

Painted frames were assembled on a separate line where chassis components such as control arms, springs, rear axle, brakes, fuel and brake lines, exhaust and the like were installed with the frames inverted. Once the frames were fully dressed they were flipped over and readied to be lowered onto the assembly line where they would get engines and transmissions and be mated to the body. GM wanted all 300 Corvettes assembled and ready for delivery by Christmas 1953. The last Flint-assembled Corvette unit rolled off the line December 24, Christmas Eve.

What hurt Corvette sales initially was limited availability of those first 300 units produced at Flint. Because availability was intentionally limited by GM management, buyers yawned and ultimately turned their attentions elsewhere. By the time GM made the Corvette available to the masses in 1954 no one cared, which made it challenging to sell GM’s two-seater.

St. Louis — Corvette’s Spiritual HomeGM’s St. Louis assembly plant dated back to the origins of General Motors early in the 20th century. The St. Louis assembly plant on the north side of the city was one of GM’s oldest plants in 1954.There were actually two plants at St. Louis; Fisher Body and Chevrolet. Ultimately, the two plants merged into one large operation consisting of a car line and a truck line. The addition of the Corvette would make three assembly lines in 1954.

Once Chevrolet wrapped up 1953 Corvette production at Flint, production was moved to St. Louis where the goal was again 50 units a day. Key St. Louis plant workers and supervisors had to travel to Flint during the summer of 1953 to see what they would be facing back home when it was time to build Corvettes. Job 1 would be right after Christmas at St. Louis.

The production launch at St. Louis was not an easy one. Aside from the usual production start-up issues automakers face; there was the issue of a backlog of unsold Corvettes. Chevrolet had an unrealistic goal of 50 units a day and 10,000 Corvettes annually. However, only 3,640 units were completed in 1954, with many left unsold from coast to coast. It was dreamy-eyed window shoppers at the Motorama shows that inspired GM to produce the Corvette to begin with. When it came time to plunk down the cash, buyers were nowhere to be found. Production was cut by two-thirds until Chevrolet management could figure out how to market and sell the Corvette.

Chevrolet considered dropping the Corvette altogether. However, when word hit the streets Ford had a two-seater of its own planned for 1955, the Thunderbird, GM continued its marketing plan for the Corvette. It is important to understand that the Corvette and the Thunderbird were never in the same two-seat class, which means they were never direct competitors. The Corvette was a true two-seat canyon-cutting sports car. The Thunderbird was a two-seat personal luxury car that sold in greater numbers because it appealed to a larger audience who wanted luxury. With this in mind, Chevrolet continued to focus on Corvette’s demeanor as a true American sports car.

The road to success for the Corvette would be a long one. In 1955, Chevrolet would sell just 700 units, a huge disappointment for GM management and Chevrolet dealers who expected better numbers, especially in light of the new V-8 available in 1955. This wasn’t great news for William Mosher, Plant Manager at St. Louis at the time.

Accommodations at St. Louis for Corvette assembly were modest and on a par with Flint. Because production quotas for the Corvette were small compared with the more mainstream passenger cars and trucks being produced on two other GM lines there, Corvette production would be at the old Fisher Body mill building on Natural Bridge Road in the St. Louis Union Avenue complex. Production at the plant made GM accountants weep at just 300 units a month at St. Louis. The Corvette just wasn’t selling. Economic conditions at the time weren’t robust, which surely contributed to weak sales. The Corvette’s inadequacies at the time didn’t help either. St. Louis, a big union town, had its share of labor issues and strikes during the three decades Corvette was produced there.

Although it has been widely reported St. Louis produced nine Corvette units an hour in those days, former plant worker Mike Dixon wrote in his Corvette book The Factory of Dreams there were just seven units produced an hour. “The line moved so slow that you had to look close as you would think it was sitting still,” Dixon said in his book. He spoke of deplorable conditions in the St. Louis plant, “I remember wearing company supplied sweat bands and taking many salt tablets that were available at all drinking fountains,” he reflects, “The summer heat was terrible, and water fights inside the plant were plentiful, as there was no A/C, but we couldn’t miss what we never had.”

Dixon went on to say, “The body drop area where I worked had a nice big glass top over it to keep us warm from the solar rays in summer. To add to the misery, we had a big slick shiny floor where the body drop men a rolled around on little stools tightening up the eight body bolts and installing the back bumpers.” Dixon went to work for GM at the St. Louis plant in 1969 and was involved in production until Corvette manufacturing ended there in July 1981. He moved on to GM’s Wentzville, Missouri plant after that.

Two companies were enlisted to produce Corvette fiberglass body parts: Molded Fiber Glass Parts Company and Goodyear, both two states away. The A.O. Smith Company began producing Corvette fiberglass in 1954 to make up for the Goodyear shortfall. Collectively, these suppliers produced the 62 pieces necessary to build a Corvette body. They had a difficult time keeping up with demand and the quality was disappointing. Body parts had to be hand sanded and filled, which consumed excessive amounts of time. GM’s in-house shop known as the Parts Fabrication Group in Warren, Michigan, filled in as necessary with fiberglass components.

General Tire would ultimately produce Corvette fiberglass employing a process known as Shrink Molded Compound (SMC), which produced super smooth fiberglass and meant less labor time for St. Louis assembly workers. Mike Dixon commented in his book on how miserable the body line was to work on because fiberglass causes horrible itching. “If you were unlucky to have been placed in the body shop, you were almost always itching, scratching and miserable,” Dixon states in his book. “The body shop was covered with dust and of course some asbestos I’m sure.” He adds many people came great distances to work there because it was considered a great job. However, working conditions were grueling.

Once Corvette assembly got underway at St. Louis, the fiberglass body panels were produced via an improved process known as the Superior Matched Metal Die process, which reduced assembly time. Despite these refinements the Corvette still suffered from disappointing fiberglass quality.

The Corvette’s frame line began on the lower level of the old Fisher plant. Frames were unloaded off rail cars and scheduled into production there. Like the Flint plant in 1953, frames were assembled in modest quantities. Engines arrived from the Tonawanda, New York, engine plant bare and ready to be dressed with generators (later alternators) along with power steering pump (where applicable), engine mounts, transmission and starter. Dressed engines and transmissions were routed from the dress-up line via an overhead conveyor to the frame line where they were secured to the chassis.

Corvette product planners wanted what they could not have in 1953-’54: a V-8. This left them with Chevrolet’s venerable in-line six. Displacing 235 ci, Chevrolet engineers took this beasty inline and gave it power-adders. The Chevrolet “Powerglide” six had been around since 1929 in all its forms and it hadn’t changed much. It made 115 horsepower with wedge combustion chambers, hydraulic lifters, low 7.5:1 compression and a one-barrel downdraft Carter carb. For 1953, it received aluminum pistons, full-pressure lubrication and press-in rod bearings.

The Corvette’s “Blue Flame” six made 150 horsepower. Compression was raised from 7.5:1 to 8.0:1 to improve power, which called for premium fuel. The solid lifters from the 261ci Chevy truck engine were lined up with a more aggressive camshaft with 0.405-inch lift intake and 0.414-inch lift exhaust. Dual valvesprings were employed to prevent valve float at high rpm. Three side-draft Carter carburetors were bolted to a cast-aluminum intake manifold. Each Carter atomizer addressed siamesed intake ports, with all three carburetors connected by a surge pipe that synched air/fuel flow.

In 1955, the Corvette got a new optional 195-horsepower 265ci V-8 with a lightweight skirtless block, state-of-the-art heads, dual-plane manifold and a revolutionary demeanor that would last for generations. Horsepower went to 210 horsepower for 1956. Through it all Corvette was fitted with the two-speed Powerglide automatic. You might be tempted to ask why Corvette didn’t get a manual transmission. Manual transmissions were considered old-hat in the mid-1950s. Automatic transmissions were viewed as high-tech. A three-speed manual transmission became available in 1956, while the four-speed came about in 1957.

The Corvette’s evolution has always been about improvement. Despite marketing struggles, GM continued to forge ahead with a better Corvette each year until sales gradually began to improve. Engine displacement grew to 283 ci in 1957 along with optional Rochester Ram Jet mechanical fuel injection to sweeten the package.

St. Louis continued to produce Corvettes even in the toughest of times when the economy and sales were weak in the 1950s. In the years to follow, Corvette production and sales would gradually ramp up, but was never robust. Production numbers surpassed 30,000 units for the first time in 1969. By 1979, numbers were in excess of 53,000 units, which is a record that has never been surpassed.

In the early 1960s, GM began asking itself how to improve on the winner it had in the C2 1963-’67 Corvette, which was a quantum leap technologically from C1. Costs for developing the C2 had been astronomical because it was so radically different. It wasn’t long into C2 production when GM began to look at the Corvette’s long-term future. C3 1968-’82 styling began with stylist Larry Shinoda’s Mako Shark II show car, which debuted in 1965 on the show circuit. Scheduled model year debut was 1968. However, plagued with lengthy development issues, the Corvette entered production with its share of problems. In due course, GM ironed out these issues and the C3 Corvette enjoyed a steady production life at St. Louis through 1981.

It was a hot, sticky summer day on July 31, 1981, when Alphonse Juergensmeyer drove the last Corvette off the St. Louis line signaling the end of an era for the riverfront community. Some 695,214 Corvettes had been produced there in 27 years. Alphonse, like so many others, was devastated by the end of Corvette production. Some transferred to other GM plants while others lost their jobs. Roughly 1,000 St. Louis workers made the tough decision to abandon their St. Louis roots and move to the new Corvette plant in Bowling Green, Kentucky. Vette