Corvettes are hardly regarded as subtle, graced as they are with a shape that embodies the essence of pure performance and instantly conveys their sporting nature. But within the world of modified Vettes, this athletic appearance alone is often not enough. Many owners choose not to keep their horsepower accomplishments a secret, festooning their cars with body kits, dazzling paint schemes, and fender-badge boasts that loudly broadcast their enhanced capabilities.

Other drivers prefer to forego the cosmetic braggadocio and undertake a more clandestine approach. Chris Weber of Brandon, Florida, is among this group. His '99 Fixed-roof Coupe has an unassuming appearance that doesn't betray the formidable power within. Still, Weber says the car wasn't built to be a sleeper. "You can't call a Corvette a sleeper, [since] they are slick-looking cars." Rather, his aim was to build a fun street car that fit his low-key style.

A lifelong motorcycle enthusiast, Weber had never been a car guy. But after he was involved in a head-on accident in 2002, he decided to leave two-wheeled conveyances behind for the relative safety of performance cars. He's tried out many artificially aspirated vehicles in the short time since then, including a twin-turbo Mustang Cobra and a head-and-cam '01 Z06 with nitrous. "Basically, I get bored with cars, and I like to move on before they need costly repairs," he says. His experimentation has given him a preference for nitrous oxide over forced induction in LS engines, since the super-cooling gas is capable of providing more performance gains for less money in these applications.

The engine in Weber's FRC comprises a highly effective suite of performance parts, all of which were chosen with an eye toward preserving reliability and daily usability while significantly boosting power. The internally stock block is topped with a set of Texas Speed & Performance Stage 2.5 5.3L cylinder heads. These retain the factory rockers but are outfitted with oversize valves and platinum dual valvesprings. The heads were set up by TSP to complement the specs of the aggressive Comp Cams 237/242 camshaft, which features 0.605/0.610-inch lift on the intake and exhaust sides, respectively. Rounding out the valvetrain are a set of Comp lifters and chrome-moly pushrods.

Intake air enters through an open-element K&N air cleaner and travels through an LS6 manifold fitted with a ported throttle body. The engine's increased fueling demands are met with 42-lb/hr injectors, while the oiling duties have been bolstered with an LS6 oil pump.

In keeping with the car's theme of subtlety, the exhaust system has been designed to scream sotto voce. A pair of TSP long-tube headers feed into a custom mid-pipe and after-cat setup employing Magnaflow mufflers. The tips are actually transplants from a Mitsubishi Evo-likely a Corvette first. The resulting exhaust note has a mellow tone that doesn't divulge the Vette's performance capabilities.

The single greatest contributor to the car's prodigious acceleration is a custom Nitrous Express nitrous system. Unhappy with the inconsistent results he had achieved with the nitrous setup on his previous Z06, Weber wanted to devise a new form of system control that didn't rely on the mass-airflow sensor. He decided to experiment with a unique idea that he'd been considering for some time.