High-horsepower performance in a convertible? John Smeelen's '06 C6 has it.
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.
GM/Katech-based LS7 is topped...
GM/Katech-based LS7 is topped by an early-production Magnacharger 2300 TVS. The combo puts out a massive 768 rwhp with about 13 pounds of boost.
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."
"Marble" center stripe atop...
"Marble" center stripe atop a vivid red base color helped Smeelen's C6 win Best Exterior at 2010's Corvettes at Carlisle. The West Coast Corvette carbon body kit didn't hurt, either.
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.