Dual Threat

This supercharged C7 coupe surmounts drag-strip sprints and nail-salon runs with equal aplomb

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August 10, 2018

New Yorker Chris Longo was utterly obsessed with fast cars as a child, a fascination that led him to purchase his first set of wheels at the age of 14. “I bought a 1971 Camaro, the first of several split-bumper Camaros I’ve had,” he recalls with a broad smile playing across his face.

Longo’s formative teenage years were in the 1990s, a time when the trend in the hobby was swinging very strongly away from modification and toward original-style restoration for vintage muscle cars. Always the rebel, Longo followed his heart and constantly sought ways to personalize—and, above all else, improve the performance of—his cars. This quest to go faster and faster was a hands-on education for the lad, and it ultimately led him to open his own performance shop when he was only 20.

“We built a lot of really cool hot rods, and my love for cars got more intense in the early years of being in business,” he explains. “But as these cars started evolving into fuel-injected monsters, and we were able to start live [computer] tuning, we were off and running. We built a ton of Camaros, Mustangs and…Corvettes, starting with C4s and continuing right on up to C5s, C6s and then C7s.”

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While Longo’s shop, appropriately called Big Power Racing, was humming right along, the advance of automotive technology was continuing apace, and the introduction of direct fuel injection in the 2014 Corvette opened up a whole new world of possibilities. Longo bought a new ’15 coupe to serve as a test bed of sorts, so he could figure out how to modify it for significantly better performance while preserving its impressive “street-ability.” Longo believes very firmly in keeping all of his street-car builds fully drivable, regardless of how radical they get from a mechanical standpoint.

“If I’m building a car that’s exclusively for track use, that’s one thing,” he opines, “and we do plenty of those, too. In fact, I have a crazy ’68 Camaro that’s a track-only car. But if a customer wants a car that’s wicked fast on the track, but will also be driven on the street, it has to retain good manners. I don’t mean it has to be able to ‘just get by’ for street use. I mean it has to be comfortable and pleasurable and easy enough to drive and live with for everyday use—going to work or school or wherever.”

Because he intended right from the start to dismantle and radically transform the C7, Longo ordered a base car rather than a new-for-2015 Z06. For the quickest shifts possible on a drag strip, and the greatest ease of use on New York’s traffic-saturated highways, he chose to go with the 8L90 eight-speed paddle-shift automatic gearbox.

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On the very first day he brought his new C7 home, and with only 127 miles on the car’s odometer, Longo and his team at Big Power Racing pulled out the original 6.2-liter LT1 and installed a brand-new, custom-designed supercharged engine. The new mill was built up from a Z06’s LT4 block, which was designed to handle the added stresses imposed by the 650-horsepower Corvette supercar. Longo’s new sleeved block was filled with the highest-quality internal parts, including a fully balanced Callies Performance Products billet rotating assembly, a custom-grind supercharger cam from Comp Cams and a set of ARP’s super-strong cylinder-head studs. The heads themselves were extensively ported and polished, then outfitted with stainless-steel valves and Cometic head gaskets. Finally, the completed long-block was crowned with a ProCharger F-1A-94 blower, a race-spec centrifugal unit capable of supporting up to 1,200 hp.

An engine that’s been modified to make dramatically more power needs dramatically more fuel, but back in 2015 there were very few fuel-system upgrades available for the new LT1 powerplant. Luckily, a company called Fore Innovations in Clearwater, Florida was in the process of developing a couple of new increased-flow fuel setups for late-model Corvettes, and agreed to work with Big Power to get a suitable system finalized.

Though Longo chose to stick with the car’s original automatic trans, he thought it prudent to beef up the gearbox to work properly with the more powerful engine. To that end, he tapped Circle D Specialties for one of the company’s stronger-than-stock HP Series Billet Stator torque converters. This modified factory converter features a stall speed that’s approximately 1,000 rpm higher than stock, allowing the blown engine to access the meat of its power band more quickly when the throttle is depressed.

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The techs at Big Power Racing made a variety of other performance-enhancing modifications, ranging from the addition of a Moroso oil catch-can to the installation of American Racing headers. They also substituted a new, free-flowing exhaust system from Billy Boat Exhaust in place of the factory system.

After getting the car back together, it went straight onto Big Power’s chassis dynamometer for evaluation. Longo was pleasantly surprised with numbers that were even better than he expected. With only moderate boost, the engine was churning out a little more than 700 hp at the rear wheels. The next move was to alter the supercharger’s pulleys to increase boost, but more boost didn’t measurably impact power output because there wasn’t enough fuel getting into the cylinders to keep up.

“We worked with a fuel-injector company,” Longo tells us, “to develop injectors that would give us 40 percent more fuel flow while maintaining the stock spray pattern. [That] was important…in order to maintain good drivability.” With the newly minted injectors in place, the car was strapped down on the dyno for another round of pulls. Running 30 percent more boost than it previously had, the new engine produced 900 horses at the wheels. Accounting for losses through the driveline, that equates to well over 1,000 hp at the crank.

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Satisfied that his forced-induction engine was correctly dialed in, Longo made the first of two trips to the track to fine-tune the car. By the end he was consistently running in the low-nine-second range. “[Those] times are all the more impressive,” he points out, “because the car is still very much a street car. We can and do drive this Corvette anywhere at any time. My wife even takes it out to get her nails done. It idles well, runs cool and never misses a beat. We really love using it.”

It’s worth noting that those quarter-mile times were abetted in no small part by the gummy Mickey Thompson ET Street S/S rubber currently occupying the rear wheel wells. Measuring a fat 305/35R19—up 20mm in width from the factory measurement of 285/35R19)—these lightly treaded radials are designed to provide maximum stick on a drag strip while returning reasonable all-weather capability. While they likely give up some lateral traction to the OEM Michelins, it’s a compromise Longo is willing to make in pursuit of straight-line supremacy.

Ever the hot-rodder, Longo plans to upgrade to a car’s differential to a strengthened aftermarket unit in the future, and he’s considering installing a wide-body kit from ACS Composites as well. Until then, he and his wife can rest easy in the knowledge that their force-fed C7 likely the fastest, most powerful salon shuttle around.

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Also from Issue 124

  • Original Split-Window racer
  • Buyer's Guide: C3
  • History: C1s invade Sebring
  • ’78 Indy Pace Car remembered
  • Restored Cheetah racer
  • Highway-conquering C1 restomod
  • Inside the LT5
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