With all the services offered by corner-lot shops and tire retailers, it's hard to know what you might actually need, and what's just an up-sell to make the shop money. However, Corvettes like the C5 aren't like other cars -- finely tuned and sophisticated, these cars absolutely depend on proper front and rear suspension settings to offer the performance, reliability and safety that GM had in mind.
Technically speaking, no car "needs" an alignment unless the factory alignment has gone out of spec for some reason. However, it's always a good idea to get your suspension alignment checked about once a year, or every 7,500 to 10,000 miles. The Corvette, with its independent front and rear suspensions, absolutely does require a four-wheel alignment check and adjustment when needed. That's not the end of the story, though, because different drivers will be happy with different suspension alignment settings. Your alignment shop will have a listing of the factory settings, but you might suggest the following settings to fine-tune the car to your driving style and requirements.
Daily Driver: These settings will minimize wear on your tires and suspension components, and maximize fuel economy. The trade-off is that the car may feel a bit lighter and more darty going over road imperfections, and you'll lose some outright cornering grip. For a daily driver, set the front suspension with 1/32-inch toe-in, 0 degrees camber and 6 to 7 degrees positive caster. Set the rear to 1/16-inch toe-in, and 0 degrees camber.
For quicker steering response: On the front, use 0 to 1/32-inch toe-in, 1/4-degree negative camber and 6 to 7 degrees positive caster. Use 1/16-inch toe-in and 1/2-degree negative camber on the rear. Expect to give up a bit of tire life over the daily driver settings.
Track Settings: This is a good baseline for maximum performance on the track, at the expense of more wear on the tires and suspension, and a bit of a drop in fuel economy. On the front, use 1/8-inch toe-out to 1/32-inch toe-in, 1/2-degree negative camber and 4 to 6 degrees of caster. For the rear, use 1/8- to 1/4-inch toe-in, and 1 to 2 degrees of camber.
