From its new and simplified electrical architecture to its fast-shifting eight-speed automatic transmission, the flashy new midengine Chevrolet Corvette is bristling with new technology. But there's one piece of high-tech innovation on the car that has no moving parts and can't be seen. It is a weight-saving game-changer that engineers from Chevrolet and Shape Corp. of Grand Haven, Mich. treated with the same gravity as the car's 495-hp midmounted engine.
It's the curved carbon-fiber rear bumper bar mounted to the frame rails.
Shape's engineers, working alongside their Chevrolet counterparts, perfected the technology that created the curved pultruded beam for high-volume production — an industry first. The bar sits behind the rear fascia and helps protect the frame rails, trunk and other parts of the car in a rear-end collision.
Most carbon-fiber components are extruded, or pushed through the die that makes the part. The Corvette's pultruded bumper bar is pulled through the die, a manufacturing process designed for carbon fiber and resin.
Toby Jacobson, plastic and composites engineering manager at Shape, said the company was in the process of developing the technology to produce the curved carbon-fiber bumper bar. But when Corvette engineers decided it would be a perfect fit for the car, the project took off.
Jacobson said GM brought expertise in design for manufacturing, computer-aided design and carbon fiber, while Shape's knowledge in materials and energy management blended well with GM's.
"They were committed," he said. "We got a lot of support from their materials team to get it approved. GM was very accessible. The testing took a lot of time, but they opened up their lab and did a lot of the materials testing and got it done very quickly. There was genuine enthusiasm from their point of view."
On the previous-generation Corvette, the rear bumper was made of aluminum and weighed about 8.5 pounds. The carbon-fiber bumper bar, which Shape manufactures and delivers to GM, weighs about 2.8 pounds. Jacobson said the previous aluminum version was not optimized for weight. On a high-performance sports car, every ounce matters because weight affects acceleration, handling and braking.
During the reveal of the midengine Corvette last summer in an old blimp hangar in Tustin, Calif., the Corvette's chief engineer, Tadge Juechter, took the rare step of calling out the unseen back-end component.
For project partners at the marketing event, the shout-out was a thrill.
"It's not the sexiest part of the vehicle," Jacobson admitted. "Consumers are not looking at that when they are buying the car."
But speaking of what was achieved through the partnership, he added, "It was pretty rewarding to all of us who worked on the car to hear the bumper being recognized."
Suppliers are partnering with other suppliers and automakers to reach their goals.