Nicholas Short owns Competition Race Parts, a company that is situated fortuitously in the heart of Cup Racing Land, also known as Charlotte, North Carolina, and environs. CRP Racing, as it is called, is actually in Harrisburg, a bedroom of the Big C. CRP wields a serious fabrication sword, capable of complete chassis and suspension construction, as well as safety cages and track-day exhaust systems. CRP builds and preps race cars. It goes much further, of course, but heed the constant: at the bottom of their CAD/CAM hearts Nick and his compatriots are demon-tweak racers.
This C6 race car resembles the street qualifier in form only. Inside, it might feel like Doctor Caligari’s cabinet, rough-hewn but elegant, altogether alien yet soothing in its simplicity, not an ounce of humor, though. It’s driven furiously for short distances and then slammed violently into a cruel arch in the track, only to recover and begin the stalking, gear-changing rant all over again in a completely new environment. There is some psychic respite in the one or two long straights where the C6 could reach its (speed-limited) 170-mph top. We watched a video showing Ron Fellows ripping up Watkins Glen from inside as well as outside the car. You couldn’t find a more perfunctory and relaxed pilot. Indeed, the only movement that stands out is Fellows’ fluid manipulation of the sequential gearbox—followed by that enchanting whine.
Nick’s yellow fang Corvette competes in SCCA’s Pirelli World Challenge Series, a 12-circuit event. In 2010, CRP had wins with Fellows at Mosport and Watkins Glen and took gold at Mid-Ohio behind Mike Skeen. Foremost, the chassis must be as safe and rigid as possible. Top that end, CRP combines an original equipment “frame” with a custom rollcage (more like a “roll-nest”) in a cell that isolates and protects the driver and facilitates the car’s awesome capabilities.
One thing about racers: when they find out what works, they’re not likely to share the enlightenment. Cam timing, spring rates, and flow rates tend to stay proprietary, but in this arena, hard parts can be as common as Cloyes double-roller timing gear or as exotic as the Holinger sequential transmission or the Xceldyne Technologies titanium valves.
Race cars are also likely to manifest one-off components. The light-metal rims on Nick’s C6 are race wheels that were developed by Cragar in a partnership with Hawk Performance and represent the only set in existence. The alliance between the companies is tight so the hoops may be marketed by Hawk rather than Cragar. The Hawk race pads were developed with CRP Racing and will soon be available on the open market.
As adept as they are at planning and fabrication, CRP leaves engine disposition to Cronin Racing Development in nearby Concord, North Carolina. The base insert is an LS2 engine. Displacement remains 364.4 ci via a 4.00-inch bore and 3.625-inch stroke. Since longevity is the key to performance in road racing, the rotating assembly includes a Callies crankshaft, Dyer steel connecting rods, and JE 12:1 pistons fitted with Total Seal ring packs. Although a COMP hydraulic roller is used, its specifications remain proprietary, but a Cloyes timing set joins crankshaft with camshaft. The miracle of CNC is visited upon the LS3 cylinder heads, thus equalizing port and combustion chamber dimensions. The Xceldyne titanium valves are wrapped with psi springs; pushrods and hardware are COMP issue. Rocker arms are tough OE. A Dailey Engineering wet sump conversion ensures adequate lubrication on the race course and allows the C6 to become intimate with the tarmac as possible for a proper coefficient of drag. Lithium Products batteries power the Bosch ignition and MoTec engine management modules. An OE composite intake manifold takes air from a 90mm throttle body and exhaust spending is extracted by PRO-FABrication stainless steel headers with 13/4-inch diameter primary pipes. As the car weighs just 3,050 pounds, the output of the LS2 has been rated at a nominal (but quite effective) 480 lb-ft of torque at 5,800 rpm and 560 hp at 7,200 rpm. To physically transfer this largesse, CRP incorporates a Tilton 51/2-inch triple-disc clutch assembly and matching flywheel. Torque is processed through a Holinger (Victoria, Australia) six-speed sequential gearbox thence to a C6/Z06 Getrag differential with 3.90:1 gears and a limited slip. This unit offers a strong, low-friction link. Final drive ratio depends on the weather and specifics of each venue. Beefy halfshafts and ends supplied by The Driveshaft Shop (Harrisburg, Pennsylvania) put the power where it does the most good—usually without fail.
Hey, it’s a race car and not liable to detail before each appearance. Road rash and battle scars all become part of the aura. In essence, the C6 is a “panel car” and wears widebody carbon-fiber parts. Ira Carlisle (purveyor to Cup teams) in Hickory, North Carolina, did the paint and bodywork. Red Eye Design (Harrisburg) applied the always-critical graphics.
It’s deceptively simple: a web of white chromoly and Race Tech custom seats sans covering; the shifter jutting from the floor was once meant for a Hurst OE application. There’s a small phalanx of toggle switches but no instrumentation save for the all-inclusive MoTec data acquisition module floating in the middle of the carbon-fiber dash and instrument panel. Mike Skeen thumbs the oddly shaped, well-worn Sparco oblong steering wheel. The small tape flap on it is to remind of something important.
Chassis & Suspension
All fabrication was charted and completed at CRP Racing and included a rollcage integrated with the chassis proper. The main rails are C5 Corvette and segue neatly into the structural rigidity afforded by the ’cage and its stringers. The less deflection in the chassis, the more accurate the steering and the better the handling qualities will be. CRP applied custom-built uprights, fitted them with SKF Racing hubs, tubular control arms, Hypercoil springs with CRP/Penske coilover dampers, and a custom antisway bar. At the rear of the C6 we find another Hypercoil/Penske agglomeration and fabricated antisway bar.
Wheels & Brakes
The relatively low mass of the C6 allows CRP to use AP 13.77-inch diameter rotors at each wheel and six- and four-piston calipers fitted with Hawk racing pads. The prototype Cragar modulars are 18x10.5 and 18x12, respectively, and host 305/645 and 315/675 Pirelli P Zero race rubber. Compound and tread (slick surface or sipes) are dictated by the course and the weather. CHP