For Corvette lovers wanting to seriously upgrade their ride's performance, a coupe (or hardtop) is usually the only way to go.

Not so with John Smeelen, who teamed with Toronto's Dream Machines to create a mega-power marvel of an open-body Vette. "I wanted to have something different, and I wanted the best of both worlds," says Smeelen of his choice to build a convertible Corvette. "You don't see very many ragtops that are high-performance, because of structural issues and so on."

Making sure the topless Vette wouldn't tie itself into a pretzel was one aspect of the project, one that would consume more than 1,000 hours of work from start to finish. But that wasn't the biggest challenge that they faced. "The hardest part, believe it or not, was the engineering of the engine, blower, and transmission," says Smeelen. "If it was a manual transmission, it would have been much simpler."

Fortunately RPM Transmissions was able to upgrade the GM 6L80E six-speed automatic and provide a pair of 1,000-hp-capable halfshafts to handle the anticipated big power.

Under the hood, the plan called for replacing the stock 400hp LS2 engine with a custom-built LS that would twist the dyno dials much, much higher. That included a Magna Charger TVS 2300 supercharger, one with a minor challenge added: It was a very-early-production piece, and likely the first of its kind in Canada. "We had to devise our own custom pulley system for the blower," Smeelen recalls.

The result was a truly one-off 50mm, curvilinear, synchronous beltdrive. This setup even incorporates an overrun clutch that eliminates the belt shock that normally results from throttle manipulation.

To further ensure durability at high boost levels, Dream Machines specified the GM/Katech LS7 block stuffed with a forged steel Callies crankshaft and plenty of other high-strength internals.

"We're running about 13 pounds [of boost], and we've designed it so that it's very, very user-friendly and reliable," says Smeelen. "We detuned it so that we could have peace of mind. There's still a lot of output—it could be greater, but we're not taking that chance."

Even at that relatively modest boost level, the engine pumps out a monstrous 768 hp and 802 lb-ft of torque at the rear wheels, enough to put even the most radical of dedicated race Vettes back on the trailer.

Other mechanical mods include Pfadt Race Engineering coilovers, huge Baer brakes, and MHT Paragon aluminum wheels shod with Michelin Pilot Sports.

But there's more to Smeelen's C6 project than just the supercharged LS7 and the chassis hardware to handle it. The color scheme not only includes a bright-red base color, but a unique center stripe with a marble-like appearance. Says Smeelen, "We decided that we were going to break up that mass of red, and we wanted to do something different, with the marble texture. It goes with the leather interior, and it takes away from some of the mass of red that the car is." It also helped it score the Best Exterior award at last year's Corvettes at Carlisle.

Also noteworthy are the car's custom structural roll hoops, which are hinged to allow sufficient clearance for the factory power top as it sweeps through its range of motion. They even incorporate override safety switches that prevent the top-up procedure from being initiated while the hoops are in the upright position.

When it comes to driving, Smeelen says you can run out of road with his '06 in a hurry. "John Edwards of Dream Machines testdrove it. He was only in Fifth gear...going 255 kph [about 158 mph], and he said, 'I'm just not even close to top speed.'"

And, like other LS-engined screamers, this C6 is an efficient cruiser, too. "I can putt along at 110-120 kph and get 10 liters per 100 kilometers," says Smeelen. (That's around 23 mpg at 68-74 mph.) "But if you want to boot it, I've seen it go up to 25 liters per 100 kilometers." (You don't want to know.)

Whenever Smeelen takes the car out, it's an attention getter. But he says that attention-magnet status comes with a price: "If you've ever been in Corvettes or exotic cars, have you ever noticed that people look and gawk at you while they're driving? They're not paying attention while they're driving—and they're almost running into you!"

Fortunately the heightened interest hasn't resulted in any on-road mishaps, and John Smeelen is still enjoying the many facets of this, the ultimate dual-use C6.

Spec Sheet: '06 Convertible
Owner John Smeelen; Ajax, Ontario, Canada
Block GM/Katech LS7 cast aluminum
Displacement 427 ci
Heads Airflow Research 225cc aluminum
Valves Titanium with hollow stems
Camshaft Comp Cams hydraulic (234/242-deg duration, 114-deg LSA)
Rocker Arms Yella Terra 1.7-ratio
Pistons Callies Compstar forged aluminum
Crankshaft Callies Magnum XL forged steel
Rods Callies I-beam forged aluminum
Power Adder Modified Magnuson MagnaCharger 2300 TVS with custom beltdrive and boost-sensitive alcohol injection
Boost 13 psi (17.5 psi max)
Intake Manifold Magnuson cast aluminum with integral liquid-to-air intercooler
Fuel Injectors Mototron 60-lb/hr
Fuel Pumps Two electric pumps mounted in fuel tank (one boost sensitive)
Ignition MSD coil-on-plug with custom DML "Hydro Pole" brackets
Exhaust System Modified Corsa stainless steel with custom stainless tips
Transaxle GM 6L80E automatic, modified by RPM Transmissions with "1,000-hp" upgrade halfshafts from the Driveshaft Shop
Torque Converter Precision Industries multiple-disc, Fast Times safety bellhousing
Driveshaft The Driveshaft Shop "1,000hp" upgrade
Suspension Stock with Pfadt Race Engineering coilovers
Brakes Baer discs with 14-in drilled/slotted rotors and six-piston calipers
Wheels MHT Paragon forged aluminum; 20x9-in (front), 20x12-in (rear)
Tires Michelin Pilot PS2; 285/25ZR20 (front), 335/30ZR20 (rear)
Fuel Octane 93
Miles Driven Daily 30-50
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