Some folks fantasize about twins. No, not that kind of fantasy. We're talking about a pair of puffers, a couple of spoolers, dual windmills. Still confused? We mean twin turbochargers, a setup that eliminates the lag on the low end and makes mondo power at full throttle.
Richard Galing knows what we're talking about here, having messed around with a few turbo imports before getting serious and building up his Corvette C6 with a bi-turbo system. His first car was an '86 Mazda RX-7 Turbo II. "I did the whole nine with HKS performance," he recalls.
Galing's FI jones quickly became habitual, with Japanese cars serving as his substance of choice. "In 1991 I purchased a Nissan 300ZX Twin Turbo, caught the mod bug, and did the Stillen upgrades. In 1994 I got a Supra Turbo and modified it with Greddy upgrades. I've been a big fan of turbo cars, particularly imports." No kidding.
He then took a weird detour into a few German sport sedans and SUVs before eventually seeing the error of his ways. After checking out a sixth-generation Corvette at the Los Angeles Auto Show, he knew it was time to get back into a two-seater. "With the all-new LS2 producing 400 hp, it was the perfect choice to dive back into a hobby I first started in the late '80s: making cars go fast with forced induction."
Once he had his own C6, the first upgrades were Kooks long-tube headers, a Borla exhaust system, and a Haltech air intake installed by Los Angeles Performance Division (LAPD) in Chatsworth, California. "LAPD's [then] owner Sean Masoudi was of great help and knowledge, as he had purchased a C6 as a test car for the shop," Galing says. "LAPD is known in Southern California for its exceptional customer service." (The company has since changed hands, so we spoke with current honcho Keith Edelen for more details on the buildup.)
But Galing still didn't have a force-fed setup. "It wasn't too long before I began to itch for more power, and the bolt-ons no longer made the car the thrill ride it once was," he admits. "The market was light on forced-induction parts at the time, but about nine months later, ProCharger released its supercharger packages." He started with the basic P-1SC kit and later moved to the more potent D-1SC package in an attempt to break the 600-rwhp mark. "Sure enough, with the supporting hardware I was able to pull 650 rwhp on an internally stock LS2 block," he says.
Big power can ruin you, though, and Galing kept his eyes out for even bigger numbers. Not much later, Air Power Systems (APS) released its C6 twin-turbo kit. Galing had the opportunity to drive a test car at LAPD, and he had one word for the experience: "Wow!" That one ride was all it took for him to change his priorities.
Blood still pumping at max boost from the experience, Galing quickly came to an obvi-ous conclusion. "It was now time to switch the supercharger for a twin-turbo setup," he says. "It's a more efficient forced-induction unit with-out the parasitic loss of a blower, and it also offers the luxury of adjusting boost pressure inside the cabin. So I drew up a parts list and commissioned LAPD-in consultation with APS-to build me a Corvette supercar."
For those not familiar with twin-turbo set-ups, they come in three basic configurations: sequential, compound, and parallel. The sequential type, designed to minimize turbo lag, uses only one of the turbos at lower engine speeds and both at higher engine speeds. A compound turbo is used to achieve extremely high pressure ratios by having one turbocharger pressurize the air coming into the inlet of another. (Due to the amount of boost involved, this type is typically found on a more robust diesel block.)
The parallel type on Galing's Vette equally splits turbocharging duties between each bank of cylinders, so each turbo is driven by one-half of the engine's spent exhaust energy. The APS unit also features liquid-cooled ball-bearing turbos that are mounted underneath to minimize heat transfer. Typically, the boost level is six pounds, but Galing's built engine handles more than double that, which required 70-pound injectors and increased fuel delivery as well. APS also supplies software to reflash the factory engine computer to compensate for the radically higher airflow.
Given that he planned to pump up the car's breathing capacity, it only made sense to enlarge its lungs, so Galing decided on a larger block (402 cubes versus the stock 364) for more torque under the power curve. Another big factor in making huge power is using optimal fuel, but even at 91 octane, a modified car is constantly on the ragged edge of reliability.
"Methanol injection has long been utilized in races, and the benefits are a plus for turbo cars," Galing points out. "I chose the Alky Control kit for its user-friendly system and [because] it's proven on many of the big-horsepower cars." LAPD prefers methanol over water injection because it vaporizes better, providing a cooler intake charge so the engine can run more boost without detonation.
After tweaking with an HP Tuners unit, the results came in: "My last dyno hit was 770 rwhp and 877 rwtq at the rear wheels on 15 psi of boost," Galing says. "That's 905 hp and 1,031 lb-ft at the crank."
For all those dramatic increases in power, though, Galing preferred a subdued color scheme. Actually, no color at all-just basic black. "I've always liked the all-black sports car-the 'murder'd out' look," he says. "It's very sinister looking and mysterious." Hence, the black wheels, the Darth Vader tint job, and the body-color emblems. Everything is black, in fact, except for one small detail. "I added the red stripe on the wheels just to add contrast with the red Wilwood calipers. The red-stripe wheels are quite popular with the import cars, referred to as a 'time attack' look."
Body mods were similarly subtle. "I did the Z06 wide fenders only, and not the entire Z06 look," he says. "Essentially the car is still a C6 Z51 and not a Z06. If the C6 Z had been available back in 2005, it would've been a no-brainer. I would've gotten it in a heartbeat." But Galing has no regrets. After all, he still got into double trouble with the twins-and that's no fantasy.