| Blending economics and emotion is a tricky business, and when Chevrolet began prepping the new C7 Corvette, it knew the development process would be one of give and take, where even the tiniest decisions could have far-reaching implications for the car. With our first full test of the C7 coming soon, here's a taste of some of those decisions made real. As with our "Five Awesome Things You Didn't Know About the Camaro Z/28" brief from earlier this year, the Corvette C7 information collected here was sourced via official GM channels and by relentlessly pestering anyone even tangentially involved with project. So soak it up, and then go forth and drop knowledge on some fools. 1) The C7 marks the first use of a "shape memory alloy wire" in a production vehicle. To save weight (approximately 1.1 pounds) and reduce complexity, the new Corvette uses a smart material wire to operate a cabin vent in the cargo area that required a motorized actuator on previous models. Triggered by the opening of the hatch, heat generated by an electrical current similar to that of a interior courtesy lamp is used to contract a wire, thereby moving a lever that opens the vent, letting air escape to reduce cabin pressure and make shutting the lid easier. Once the hatch is closed, the current cuts off, the wire returns to its original shape, and a return spring closes the vent to maintain cabin temperature. GM has earned 247 patents for smart materials such as this over five years of research and development, and it figures there are approximately 200 motorized systems in the typical vehicle that could be replaced with smart materials. Typically made of copper-aluminum-nickel or nickel-titanium, smart materials can change their shape, strength, and/or stiffness when acted upon by heat, stress, a magnetic field, or voltage, and return to their original shape when the trigger is deactivated. 2) The C7 is the first-ever production Corvette with a rear weight bias. Although Chevrolet claims a straight-up 50/50 weight distribution, our scales demonstrated a rearward weight bias, with 49.4 percent sitting over the front axle and 50.6 to the rear. And, yes, we're aware the C6.R competition Corvette also tipped the scales to the stern; we're talking strictly production models. 3) The C7′s eLSD (electronic limited-slip differential) goes from open to full lock in tenths of a second. Dubbed eLSD in GM speak, the suggestively named diff comes standard with the Z51 Performance Package, and employs a hydraulically actuated clutch that infinitely varies the amount of engagement, going from open to full lock in tenths of a second. Fully integrated with the stability-control and Performance Traction Management systems, the system controls the differential according to an algorithm that factors in vehicle speed, steering input, and throttle position. 4) Corvettes equipped with an automatic transmission or Z51 Performance Package get functional vents and rear-mounted transmission and differential heat exchangers. Multiple heat exchangers are a given in this segment. What's notable about the C7′s are their rear mounting positions, which moves weight rearward and eliminates some of the plumbing (and likely shaves some pounds) in comparison to the C6 pieces. The vent on the driver's side rear fender directs air over the transmission heat exchanger, while the corresponding vent on the other side directs air over the eLSD cooler. Both exhale the air through aircraft-inspired taillamp vents and outlets in the lower rear fascia. 5) A NASA-developed insulation called Aerogel is used on the transmission tunnel. Many owners concur that the center tunnel in the C6 can get toasty, and with the C7 now locating the exhaust in an even tighter space, the potential to exacerbate the problem is very real. To combat this, Chevrolet is using insulation made from Aerogel, a material developed by NASA for use in space suits. Considered for years to be the lightest solid material in existence, Aerogel is 99.8 percent air (thereby replacing the liquid portion of a gel with a gas), yet it insulates 39 times better than the best fiberglass. The C7's tunnel has a 10-mm (0.4-inch) layer of an automotive grade version of the stuff applied to its sides, and another 5 mm (0.2 inch) on top. Hip, style-conscious owners may want to wear vintage space-suit pants whenever possible.
6) $50K was the price target from the beginning. From day one, Chevrolet was eyeing $50K for the C7's base price. Targets change, but considering the amount of tech (including new seats!) packed into the C7, drawing the final line at $51,995—just $1400 more than the 2013 C6—is more than impressive. It no doubt required some sharp pencils and tough decisions, but it's difficult to tell where pennies were pinched. Bravo. 7. It's the 30-mpg supercar. You may have missed the recent news that the C7 earned an official EPA highway estimate of 29 mpg, and that it will actually return 30 mpg on the highway cycle with Eco mode selected, which enables the small-block V-8′s cylinder-deactivation system. GM claims direct injection, active fuel management, variable valve timing, and an advanced combustion process all help achieve this efficiency. It helps that the Corvette team put in serious work, too: The engine alone underwent more than 10 million hours of computational analysis, including more than 6 million hours on the combustion system. 8. No more cross-drilled rotors. Equipped with Brembo brakes, the C7 ditches cross-drilled rotors for new discs vented by means of shallow grooves. Race teams were reporting cracking issues with the drilled units, while the new setup also maintains the benefit of better brake feel versus solid rotors, as the gasses don't push back against the pads. 9. It wears some pretty special shoes. Partner Michelin was selected as the OEM supplier for C7 rubber after a tire-company shootout, and it worked directly with the Corvette team for 36 months to create tires for the base car and the Z51 package. Michelin characterizes the resultant Pilot Super Sport ZP footwear as a cross between two of its best models, the PS2 and the PS Cup. The rubber is also among the world's first street meat to be engineered using the exact same computer models used to create tires for Le Mans and ALSM racers, and incorporates many of the same rubber mixes in its construction. 10. The tires feature asymmetrical sidewalls. Michelin has employed asymmetrical sidewalls since the first ZR1 run-flat radials, and this technology continues in C7. The inside walls of the tires are 3 mm (0.12 inch) thicker and molded with a stiffer construction to optimize comfort and cornering adhesion characteristics. The new Michelin radials also have 150 different constituents in their tread compounds.  from Car and Driver Blog http://blog.caranddriver.com | |||
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