For a $19,990 base price, Factory Five supplied Bentzel with most everything he needed to build his own GTM. The backbone of the package is a computer-designed, ultra-rigid space frame made from precision-laser-cut, high-strength, mild-carbon steel and incorporating an integral six-point rollcage with roof-contoured bars (for additional headroom in the cockpit). The hand-laid, laminate composite body panels are made with vinylester resin and black gelcoat, and include a hinged-and-lined rear hatch, doors, and a nose. More than 80 CNC-cut, pre-formed, 6061-series-aluminum panels form the cockpit, the trunk, the radiator surround, the engine bay, and the nose/splash guards.
The kit didn't stop there. Front and rear Koni coilovers, a high-performance manual steering rack (Bentzel ordered his GTM before power steering was added to the options list), a Wilwood clutch-and-brake-pedal assembly, triple master cylinders, brake lines and fittings, a radiator-adapter kit, and an optional Kooks exhaust system (comprising of 1 3/4-inch-primary headers, an X-style crossover pipe, and 3-inch stainless-steel pipes) were also included.
According to Factory Five, "The GTM Supercar kit is engineered to be built as a chassis kit by a car guy at home with regular tools. [We] give you everything you need to build your car, except for select running-gear parts taken from a '97-'04 C5 Corvette. The major Corvette parts include the engine, front and rear control arms, suspension/brakes, and fuel tanks. The only exception is the transaxle, which is a '90-'98 Porsche 911 G50 unit."
Bentzel ordered his GTM kit in April 2008. Since the delivery estimate was six weeks, it allowed him the time he needed to find a suitable C5 donor car. (GTM says that customers can also get the majority of the Corvette parts they need for the build new from GM Performance Parts.)
"After searching locally without success, I started looking on eBay," Bentzel confides. "About three weeks into my search, I found an interesting prospect in Alabama. It was an '02 that ended its life upside down in a hay field and was later sold at an insurance auction to a salvage yard. [The salvage yard] removed all the usable body parts, interior, and so on until it was down to a rolling/running chassis. Since I wouldn't need much more than that, it was an almost-perfect donor. I won the auction and had the chassis shipped to my home. When it showed up on a full-sized car hauler, my suspicious neighbors knew I was up to something."
Bentzel pulled the 350hp LS1 from the donor, disassembled its chassis, sold the torque tube and transmission, and scrapped the rest of the parts.
On June 6, 2008, the GTM kit arrived in a semi truck. In addition to the chassis and the five-piece body, there were 18 cardboard boxes packed with everything else Factory Five provides and a 2 1/2-inch thick, 600-page assembly manual.
The next day, Bentzel began the project. "Things start to go together rather quickly," he recalls. "In just a few days, I had the Corvette suspension pieces mounted, the calipers and rotors assembled, and the coilovers installed. Then came the dozens of aluminum close-off panels that needed to be drilled and mounted with hundreds of pop rivets. My forearms started to look like Popeye's," he says.
He then moved on to the pedal assembly, the Corvette's drive-by-wire throttle, the brake and clutch lines, the wiring, the engine-cooling system, the A/C, the fuel tanks and lines, and even more riveting.