Why Were Corvettes Made Of Fiberglass? (And Is It Still Used?)

Chevrolet's Corvette launched way back in 1953, and has endured a story of constant improvement ever since then. Now in its eighth generation, a lot has changed for the Corvette. In addition to the fact that Corvettes are now mid-engine, have been hybridized, and are also available with all-wheel drive, the body is no longer heavily reliant on fiberglass either. For decades, this was the material of choice for America's favorite sports car, and the reasons for choosing fiberglass were really quite simple.

Chiefly, fiberglass is cheap. This was especially important to GM when developing a low-volume sports car, the success of which it couldn't have imagined when first developing the C1 — that's the generation of Corvette that features in the TV show "Lucifer." Rather than investing in pricey sheet-metal stamping dies, GM opted to use fiberglass, enabling it to construct a lightweight sports car without excessive financial outlay. There lies the material's second huge benefit, too — lightness. Using fiberglass body panels was a brilliant way for GM engineers to keep the weight down, which in turn would benefit performance, and that's no bad thing for an all-new sports car designed to capture the imagination of motorists in post-war America. 

The Corvette turned out to be a huge success, and therefore, GM saw little reason to mix up the recipe. As a result, Chevy continued to use fiberglass body panels on the beloved 'Vette for some time, although technical innovations along the way have reduced how much the automaker relies specifically on fiberglass.

The first big change in Corvette construction came in 1968, when Chevrolet moved away from old-school methods and adopted a press-mold process. This change was introduced when creating the Corvette C3 generation. In '73, Chevy made another notable change to the production process. This year saw the automaker move away from conventional fiberglass and start using sheet-molded compounds instead, otherwise known as SMC. This new material still featured fiberglass, but combined with resin and a catalyst, and then formed under heat and pressure. These panels were smoother right out of the mold, which meant they were easier to finish into a sale-ready state.

While the exact make-up of these SMC panels has changed somewhat over the years, Corvettes still use SMC panels to this day. Later models, such as the C6 that arrived in 2005, began saving weight in new ways. The chassis switched to aluminum, and carbon fiber would start featuring more and more from this point. So, while America's favorite sports car may have moved away considerably from its rear-wheel drive, front-engine, naturally aspirated, and fiberglass-reliant roots, it still prioritizes weight loss through lightweight materials. The end goal is still a driver-focused sports car that can give European rivals a run for their money, and usually for a fraction of the cost, too.