"As you see the marker to turn in to your left, you get on the gas lightly while changing your vantage point to the apex you're about to hit. Once you feel the car is 'seated in' and planted, you start to apply more and more throttle until you are flat out. As you go around Turn 2, it feels like the wheels are going to break off the car. It is amazing!"
Given the amount of racing she does-both at the drag strip and on the road course-it's not surprising that Cemo has upgraded her Z06 with a carefully selected assortment of high-performance and competition-spec parts. Starting with the suspension, the Z was lowered 2 inches via cut bushings and suspension bolts. Stock springs and Bilstein heavy-duty shocks reside on all four corners, while GM Performance Parts T1 sway bars enhance the C5 to almost Zen-like oneness with the track.
While suspension prowess is great for cutting lap times, the extra power needed to pull the Z06 out of corners or bury the tach on the back stretch provides a more visceral and immediate thrill. The stock LS6 block and heads in Cemo's Z are untouched, with the exception of a more aggressive camshaft and race-proven valvetrain components. Motorsport Technologies in Houston installed one of its custom-ground G1 cams, which boasts 228/232-degree duration, 0.588/0.575-inch lift, and a 113-degree lobe-separation angle. Manley double springs and titanium retainers work in concert with Motorsport Tech chrome-moly pushrods and factory 1.7 rockers to manage valvetrain events
A Donaldson/Blackwing air filter and smooth bellows feed air into the engine, where it is directed to a stock MAF, 78mm throttle body, and intake. Although potent in naturally aspirated form, with almost 418 rear-wheel horsepower, the diminutive 346 morphs into a real beast when squeezed with a 150-shot of nitrous. A Nitrous Express GM EFI Dual Nozzle kit, installed by Mike Pabon of Icon AutoSports in Houston, was plumbed in between the smooth bellows and throttle body and linked to a Nitrous Outlet digital window switch. Amazingly, a stock C5 fuel pump and injectors meet all of the fueling demands of the gassed engine.
A set of Kooks 1 7/8-inch stainless headers are mated to a Kooks 3-inch mid-pipe equipped with high-flow metal-matrix converters and cutouts. For non-race activities, the exhaust is routed to a Corsa Pace Car 2 1/2-inch after-cat exhaust with Pro-series tips. An SLP 160-degree thermostat and a Ron Davis Racing aluminum radiator with integral oil cooler manage engine heat during racing events. Motorsport Tech's Jayson Cohen is credited with tuning the stock PCM to ensure that the motor remains healthy both on and off the bottle. Other than some MSD 8.5mm plug wires and NGK TR-6 plugs, the ignition system remains stock.
While road racing is generally easier on driveline hardware than drag-strip flogging, the extensive nature of this Z06's performance usage necessitated upgrades all around. Shifting duties are handled by a T56 six-speed transmission reassembled by Houston-based T56 Rebuilds after a 6,200 rpm shift on slicks annihilated the mainshaft. A Hurst short-throw shifter and MGW Gripper knob provide harmonious rowing action, while a Textralia OZ-700 single-disc clutch and flywheel transmit power to the pavement. Other than a Dynotech hardened output shaft, the rear differential remains stock, right down to the GM 3.42 gears.
Whether cruising the streets of Houston or towing a race trailer to the next road-course event, Stephanie Cemo has her sights firmly set on the next level of competition, be it in the SCCA's T1 class or as a full-time driver in a professional series. Given her ferocious dedication and ability to out-handle, out-brake, and just plain out-drive her counterparts, we wouldn't bet against her.