Quad Turbo C5 Corvette: Twisted Vision

03/29/2024

Quad Turbo C5 Corvette: Twisted Vision

03/29/2024

This past fall we took an in-depth look at Twisted Speed and Performance’s wild C10 pickup, a mid-engine, twin-turbocharged monster that was originally envisioned as a relatively simple LS swap project for the company’s parts hauler. But as founder Shawn Lavrick explains, it wasn’t the first build that saw the Louisville, Kentucky-based shop venture off the beaten path. That honor goes to this quad-turbocharged 1998 Chevrolet Corvette, a car Lavrick purchased from a friend in completely stock form as his daily driver back in 2020. The project would end up inspiring him to start a performance tuning business of his own.


“We had a couple of tuners who were working on a twin-turbo setup for the car at the time,” he recalls. “We were having some trouble getting it dialed in; these guys were telling me it was ‘too much turbo’ for the car, and that’s why it wouldn’t spool properly or make the power we were expecting on the dyno. It got to be really frustrating – it just seemed like these shops were too busy, or they weren’t willing to help. So I kind of had to teach myself, and that eventually led my best friend and I to start Twisted Speed. He’s a welder and I’m a mechanic, so it worked out nicely.”

Lavrick identified some minor issues with the Corvette’s engine combination and swapped in smaller turbos for good measure, which he says largely addressed the issue. Although the boosted setup elevated the fun factor substantially, the lingering problem was that the build still wasn’t rowdy enough to meet his expectations.


“One night I was just thinking about what to do, and I was like, ‘These two turbos are spooling just fine – why don’t we add two more?’”


He says that led him down a rabbit hole of turbo research that included no shortage of videos created by Gale Banks of Banks Engineering, a legend in the field of turbocharging. “He had a project where they were doing a compound build on a gasoline engine, and that got me thinking about how cool it would be to do a twin compound setup on my Corvette,” he says with a laugh. “And I just kind of ran with that.”

After installing a beefed up 4L60E gearbox from RPM Transmissions, he set to work on the Corvette’s LS V8, which is now outfitted with a Callies crankshaft and H-beam connecting rods, Wiseco pistons, a BTR Stage 3 Turbo camshaft, FIC fuel injectors, and a Holley Hi-Ram intake manifold.


The forced induction setup consists of a pair of 61mm ON 3 turbos that feed into a second pair of 75mm ON 3 turbos. Lavrick says it’s a combination that offers roughly 1600 horsepower on 32 pounds of boost, though he notes that they typically dial it down to about 20 pounds to make it more drivable, which in turn yields about a thousand horsepower.


A Holley Terminator X Max ECU is also on board to manage the operation. “We use either a Holley Dominator or a Terminator X Max on everything we build,” Lavrick tells us. “We know that we’re not going to run into any problems with these systems – they always work great.”

The Corvette now rides on a set of Weld Racing wheels, while its hunkered down stance comes courtesy of Silver’s coilovers. To accommodate the turbo setup and its associated plumbing, the team created a custom multi-piece hood design out of a factory C5 hood, while the quarter panels and rear bumper are all one piece of molded carbon fiber. A custom roll cage, Kirkey Racing seats, Braum harnesses, an NRG quick-release steering wheel, and a Holley EFI Pro Dash give the C5’s cabin a purposeful, no-nonsense vibe.


Although LS builds were the core focus of the company’s initial projects – as evidenced by this Corvette as well as the aforementioned C10 – he says that high-horsepower Mopars have become a much bigger presence in the shop as of late. “We do a little bit of everything these days – one day we might be working on a drag car, and the next day we’re working on a show car, or a drift car. I think that versatility has become one of our biggest strengths. But the Hemi stuff, in particular, has gotten really big for us over the past year or so. We recently built a record-setting 2000hp twin turbocharged Jeep Grand Cherokee Trackhawk – as of right now, it’s the world’s fastest Trackhawk. And we’re currently putting together a donk-style ’74 Chevrolet Caprice that’ll debut at SEMA later this year – it’s all-wheel drive, tri-charged, and Hellcat swapped.”

Although the C5 build was already in progress before he started the company, Lavrick says that along the way it became something of a rolling billboard for the business and what the team can do. While he admits that it gets driven less often that he’d prefer due to the shop’s busy schedule these days, the Corvette has made the rounds at a wide array of events over the past few years and has helped to showcase what Twisted Speed and Performance is all about.


“These builds aren’t really designed around a specific goal or purpose – I just like to follow through with the ideas that pop into my head,” he says. “More than anything else, it’s just a badass street machine.”

author

251 Posts