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by Barry Kluczyk  More from Author

The Latest Velvet Hammer From Specter Werkes

As American icons go, the Corvette is one of the biggest – ranking right up there with a bottle of Coca-Cola and a pair of Levis. But more than its bred-in-America heritage is its reflection of the American psyche; it is manifestation of our desire for individuality.

Conveying individuality through the Corvette isn’t always easy, because tampering with its design can all too easily result in trampled heritage. Corvette builder and racer Jeff Nowicki, of Specter Werkes/Sports, is keenly aware of the balancing act required to enhance the Corvette while simultaneously honoring its heritage. He’s been working at that balancing act for about a decade, designing exterior enhancements and delivering increased performance both from the engine compartment and chassis.

Nowicki honed his skills with a made-to-order run of C5-based Corvette GTR models. These supercars featured wider replacement front and rear fenders, as well as correspondingly widened fascias. Each GTR had a more dramatic “Coke bottle” silhouette, which helped dramatize its bodyside lines and cover wide rubber, but the casual observer had to look twice to see the difference – unless the GTR was parked next to a “skinny” C5.

The GTR was a complete, turnkey car offered through two exclusive Chevy dealers, but Specter developed a group of ala carte exterior, interior and performance upgrades under the Group 5 label. These weren’t – and aren’t – simply the GTR components offered to the DIYer. The Group 5 components consist of unique ground effects, fascias, spoilers and other components. And rather than sell through a couple dealers, the Group 5 parts were offered to anyone who wished to order them directly or drop his Vette off at the Specter shop for up-fitting.

Recently, Specter Werkes launched the Group 6 lineup for the sixth-generation Corvette. Like the C5 GTR and Group 5 lines, the Group 6 collection is centered on exterior enhancements, with fender flares and an appropriately sized rear spoiler. It’s also a Z06 fighter, as Specter’s prototype car pumps out more than 500 normally aspirated horses from the 6.0-liter LS2 V-8.

Like the GTR and Group 5 designs, the Group 6 complement of exterior upgrades embellishes the factory’s form without outlandish exaggeration. But where the C5 exterior components offer a smooth, tailored look, the Group 6 has a harder, racetrack demeanor, owing to the C6’s racing-derived development and consequent reflexes.

“The basic form of the C6 is a racecar and the Group 6 components build on that,” says Nowicki.

The success of Corvettes, including the LeMans-winning factory team, on the racetrack undoubtedly influenced the Group 6’s design. Several of Nowicki’s customers have left cars at the shop with instructions for Specter Werkes to give them the look of a road-going racecar.

Well executed in form and proportion, the bolt-on Group 6 parts include an extractor hood, aero package with rear spoiler and rear wheel flares. The silver prototype in our photos wears HRE 840R wheels wrapped in Michelin PS2 rubber, sized 275/35/19 in front and 335/30/20 in the rear. 

The exterior appointments and serious rolling stock give the Group 6 a decided and intentionally aggressive stance. The front chin spoiler is functional, channeling air to the brake ducts, while also giving the car a “meaner” look. The rear wheel flares allow 12-inch-wide tires to fit within the bodywork.

Specter Werkes/Sports offers the individual components of the Group 6 package separately.

Naturally Aspirated


With the willing, 400-horse LS2 as a starting point – which includes elements of the previous LS6 engine, including the cylinder heads – the Group 6’s engine was treated to Specter Werkes’ “Matrix 1” makeover that included a special-grind camshaft, CNC-ported cylinder heads (with larger valves), a Lingenfelter cold-air box, LG Motorsports long-tube headers (with 3-inch X-pipe), a pan full of Mobil 1 oil and long-tube headers blowing into a Corsa exhaust system. It’s a relatively simple combination that, while requiring some careful tuning for optimal performance, delivers 525 horsepower and 435 lb.-ft. of torque.

This is racecar horsepower and time-warping torque. Besides the output, however, is the Group 6’s rumble and idle quality. It barks to life with a raspy growl, thanks to the long-tubes and Corsa pipes, but it settles into thumping, low-rpm idle that instantly reminds us of the solid-lifter days of Corvettes of a different era. There’s spine-tingling quality to the idle, too. It isn’t an old big-block, but there’s an aural cue that certainly reminds you of it.

With 500-plus horsepower, the Group 6 has no trouble hazing the nubs off the new Michelin PS2s. Throttle response is more immediate, too, thanks to a few well-placed taps of the laptop keyboard.

Surprisingly, all this power is channeled through an otherwise stock drivetrain. The cooling system is stock and so is the six-speed manual transmission, as well as its clutch. Nowicki says all of these components are more than up to the task asked of them by the pumped-up LS2.

Those with a stronger need for speed can order up a stroked Matrix II powerplant, a 7.0-liter C5R-derived engine and a Matrix SC engine equipped with a Maganacharger blower. These upgrades aren’t exactly spare-change options, but as axiom goes, speed costs.

The full Group 6 treatment also includes suspension and brake enhancements, including Stop Tech ST-60 brakes, with six-piston front calipers and four-piston rear calipers clamping down on drilled rotors – including huge 330-mm (13-inch) front rotors. The suspension receives the T-1 upgrade kit from GM, which includes new front and rear springs, stabilizer bars, upper and lower front A-arms and stronger links.

Inner Style


Along with the exterior and performance upgrades, the Group 6 package also includes a sumptuous upholstery upgrade, with Spinneybeck Italian suede. The burgundy-color material, embroidered with the Group 6 emblem on the headrests, adds a decidedly upscale aura to the Corvette’s cabin, complementing the 525 horsepower in true velvet hammer form.

All told, the exterior, interior and performance enhancements of the Group 6 – including installation, tuning and paintwork – run about $30,000. Even with a brand-new Corvette, that’s less than the cost of a new Z06. There’s also the intangible quality of exclusivity – not too many other enthusiasts will have one.

What we really like about the Group 6 lineup, however, is the cafeteria-style options. Don’t like the extractor hood? Leave it off. Want everything but the T-1 suspension? No problem.

While the quantifiable traits of the Group 6, such as the Matrix I engine’s dyno numbers or the skid pad performance of the T-1 suspension and Michelin PS2 tires, are easily justified, the intangible traits are the package’s real strengths. The hunkered-down stance, just-try-me idle quality and race-ready form are simultaneously unmistakable and understated.

Nowicki’s track record (pun intended) is strong and well established. His C5 GTRs are likely on their way to collector status and the Group 6 collection demonstrates that subtlety is often the most effective manner in which to make a powerful statement.


Specter Werkes/Sports

Troy, Mich.

(248) 583-9559




Jeff Nowicki and Specter Werkes/Sports: A Look Inside


For nearly 17 years, Jeff Nowicki has built a reputation building Corvettes from his facility in suburban Detroit. He founded Specter Werkes/Sports in 1990 and today, it not only builds Corvettes and parts for Corvettes, but also does design work and prototype building for the OEMs. The company also includes vehicles such as the Cadillac CTS in its enhancements repertoire.

Not bad for a guy who started out working for various prototype shops, as well as GM Design, while taking side projects after hours. 

“It all grew of out the work I was doing outside of my regular jobs,” says Nowicki. “I had the shop going while I was at GM and it just became clear that this is what I needed to do.”

Design work was in Nowicki’s blood. His father, Ron Nowicki, worked at GM Design for 36 years and was the chief studio engineer for the C5. By January 1998, Specter Werkes built its first GTR, which is still owned by its original owner – Chevy dealer Jeff Cauley. About 30 of the exclusive cars have been built since, along with countless other special customer projects, racecars and Group 5/Group 6 cars.

The Specter Werkes shop typically contains three or four cars in various stages of construction. On our recent visit, the projects included the GTR conversion of a 2004 Corvette Z06 Commemorative Edition, which when finished, will still wear the factory-style blue paint and graphics. It is the third GTR built for an enthusiastic Colorado customer.

“Customers are extensions of our team,” says Nowicki. “We invite them to track day events and other get-togethers. It’s like a fraternity of like-minded enthusiasts.”

At track days, Nowicki is as much a participant as host. He holds four SCCA divisional autocross championships, two SCCA road-racing championships and has participated in everything from World Challenge to the 2004 Grand-Am Rolex series.

But even the best customers aren’t privy to the OEM design work that goes on at Specter Werkes. In fact, there were parts of the Specter facility we couldn’t photograph; the curtained areas that contained ongoing modeling and prototype work. He is famously and rightfully protective of this work and no one simply waltzes back to the shop’s work area without his knowledge or escort.

The bottom line is Specter Werkes/Sports’ products are extensions of Nowicki. He embodies the realm of the Corvette world he serves, as he is as much a participant as entrepreneur.

We can’t think of a more appropriate way of doing business.


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