Corvettes were designed to go around curves. Sure, they go fast in a straight line, too, but there are lots of cars—lots of American cars—that do that as well. It's the handling that separates the Vette. Unfortunately for those of us who are enamored of the early cars, neither ever-increasing performance standards nor aging components have been particularly kind to our rides. Having already upgraded the brakes on "Scarlett, our 1972 Chevy Corvette Coupe project car, it was time to go through the suspension, starting with the front. Since the suspension of the Corvette was virtually unchanged from '63 until almost the end of the third generation, all of these modifications apply equally to midyears as well as sharks.
Before we get into the nuts and bolts of things, though, one of the biggest changes you can make in the handling is by changing the wheels and tires, and that's what we did first. Unlike the C2, which has seriously limited room under its bodywork for wide tires, the shark has plenty. Measuring carefully to get the maximum amount of rubber under the car with the minimum amount of interference, I settled on a set of Summit Racing Legend wheels in a 17x9-inch size for the both the front and the rear. They're visually similar to the classic gray-center, five-spoke wheels that appeared on many of the early race Corvettes, making them an excellent aesthetic fit for our '72. And thanks to the addition of a couple inches of wheel diameter—while keeping the outside diameter of the tire about the same—they allowed us to significantly reduce the amount of tire sidewall employed.
Much of what you deal with anytime there's rubber in the suspension is deflection: When things get "loaded," or have force put on them, rubber tends to give. When it's the sidewall of the tire, that deflection changes the radius at which the car negotiates curves. Suppose you're going into a hard right turn: The tire wants to stick the pavement, while the cornering forces on the wheel push against that, to the left. Since the tire is flexible, it doesn't track straight in the direction the car is going, but tends to "walk" toward the outside of the turn, meaning the car travels in a wider radius than you want it to. Reducing the amount of sidewall makes the car track straighter, since there's less sidewall to flex, and it also offers a much more positive feel. The downside, however, is that it makes the car's handling less forgiving, since you have less warning before the tire loses traction and begins to slide.
Obviously, we picked a wider wheel (the factory rims were 15x8 inches) in order to use wider tires, since more rubber on the road means more traction. For Scarlett, we selected BFGoodrich G-Force Sports, again supplied by Summit Racing, in a 275/40-17 size. When you consider that the stock tire was only around 215mm wide, you get the idea of how much larger a contact patch these BFGs create—something like an extra 2.5 inches of tread width. Wide front tires give great bite when you first turn into a corner, but also have a tendency to track changes in the roadway, so you have to pay close attention to keep the car from wandering.