The familiar line is that all Corvettes are red. Although not literally true, it does convey the red-blooded passion Corvette owners feel for their cars. In Rebecca McCarty’s case, though, her 2016 Callaway SC757 qualifies on both counts. Not only is it an intense shade of crimson, but she’s also a hard-driving enthusiast, with crisp driving skills honed at numerous track events.
We came across Becca, as she’s called, and her “Lipstik” Corvette, as she calls it, at Mid America’s annual Corvette Funfest. Not wanting to exclude her accommodating husband from our coverage, we invited him along for the shoot, but he declined, insisting that the car is all her deal, and asked to remain anonymous.
Indeed, “Lipstik is my vision of what the C7 Z06 should be,” she says in a southern drawl as sweet as pecan pie. “A lot of thought went into ‘her’ design.”
When we complimented her on all the integrated enhancements, she claimed, “Yeah, I wanted to keep it subtle.” Well, that wouldn’t be our word choice after seeing all the eye-popping upgrades, especially the sultry Jessica Rabbit murals air-brushed by Steve Ray under the hood. But no matter, it’s all in good humor.
How did Becca come to be so committed to Corvettes? It all started at an early age. “My 4th-grade teacher owned a Corvette, who parked it in the teachers’ lot next to Columbiana Elementary school, in the small town of Columbiana, Alabama,” she recalls. “I remember getting off the school bus, heading into school and always glancing to the right so I could view that ‘space ship’ as I walked into school.” (Incidentally, her teacher’s Lynndale Blue 1967 Corvette coupe was featured in the June 1998 issue of Vette magazine.)
That was just the beginning of her automotive experiences, as later on she lent a hand in her uncle’s pit crew, who built a car to compete in NASCAR races at Talladega. “We had a blast and I became an avid race fan, which continues to this day.”
As for how she got into a Callaway, Becca was participating in the HPDE (High Performance Driver Education) school during the 2015 Bash, held at the National Corvette Museum Motorsport Park track.
“I overhead guys talking, and Callaway announced their SC757 package for the C7 Z06,” she says. “I had already put down a deposit for a 2016 Z06. During lunch I drove my 2014 C7 that I was using for the HPDE to the NCM and talked with Chris Chessnoe of Callaway about the new car.” Not one to hold back, she ordered the Callaway SC757 package that same day.
For those unfamiliar with this impressive performance machine, it boasts a Gen III supercharger that’s nearly a third larger in displacement than a stock Z06’s (2.3 liters versus 1.74 liters). Not only that, it’s also a TripleCooled design that minimizes heat sink for better air density and thus higher power. The result is an output identified in the car’s numerical designation: 757 horses. That’s 107 bhp more than the factory Z06 output; more than enough to really get your attention.
To maximize airflow and density, Callaway engineers reworked the configuration of the company’s liquid-to-air intercooler used on the 2012 Callaway. They started by inverting the Eaton 2300cc TVS rotor pack assembly so the charge-air flows upward instead, and through a primary intercooler, and then exits into the top section of the supercharger housing. Since the housing is exposed to outside air through an opening in the hood, this setup provides additional cooling.
Channels inside the housing with heat-dissipating ridges route the airflow back down toward the cylinder heads, around the sides of the housing. A pair of secondary intercoolers provide additional heat transfer, making for a total of three, hence the “TripleCooled” name. The intercooler coolant circulates through a heat exchanger mounted in front of the radiator. All told, Callaway’s patented Gen III supercharger design delivers a much cooler charge, allowing a higher manifold pressure, and thus more power.
There’s another engineering benefit in addition to an improved intercooler system. Due to the Callaway blower’s larger volume, the drive ratio is 11 percent less than the OE’s ratio, yet increases the inlet-port gauge pressure by 25 percent. Driving the assembly at a lower speed not only generates less heat but results in less mechanical strain on the supercharger assembly and engine.
Even with all these enhancements in airflow, Callaway did not need to go with bigger injectors, but instead recalibrated GM’s engine management system. The fuel delivery capability of the OE system hardware can support Callaway’s power level.
Dyno data confirms the improvements of Callaway’s design, as inlet-air temps increase by less than one third of other supercharger systems (10 degrees vs. 35 degrees), company engineers say. Ditto on the track, where Callaway recorded a decrease in inlet port temperature of 20°F over the OE configuration, measured during identical interval points at wide-open throttle, full load, and maximum attained velocity.
Yet the fuel efficiency remains virtually unchanged from the factory’s EPA rating. This achievement is due in part to a low-restriction intake system with an internal bypass that diverts the inlet airflow during idle, low-load cruising and deceleration, allowing the supercharger internals to spin freely.
As mentioned at the outset, Becca put her own personal touches into the Callaway SC757. And not just to make it look prettier. She started on the back end first with an eye toward not only visual impact, but also better performance.
“The diffuser is what I thought the rear of the Z06 should look like,” she notes. “One color and more aggressive. Not only is the diffuser visually attractive, it has a purpose of downforce when on the track.” She had Steve Hawkins paint and install the diffuser, supplied by RKSport.
The exhaust is from Akrapovic, and Ben Herndon of Weapon X assisted her with this purchase. “I wanted a more aggressive sound but wished to retain the NPP (dual-mode factory option).”
As for the carbon-fiber trim, that’s all from APsis USA. She chose this product line because of the integrated spats that start at the front and flow into a splash guard around the front wheels. Other carbon-fiber enhancements from APsis include the splitter, side skirts, vents and spoiler, along with some interior pieces (except for the OE dash). Ruby LED accent lighting adds some bling in the grille and extractor. Ebony accent paint runs from behind the Transparent Tara top and continues to the rear of the hatch.
“It came about as I felt it made a black ‘bubble’ on top and the lines flowed better,” Becca says. She had this same treatment done in vinyl wrap on her 2014, but with her new Z06, she had it painted instead. For protecting the finish, Xpel’s body film was installed by Rory of Proven Automotive Concepts.
Even though Becca’s husband stayed out of the project for the most part, he did have the wheels painted matching red as a surprise while she was on an NCM trip to Paris and Le Mans. Although he meant well, her initial reaction didn’t meet his expectations. “I was not happy when I first saw them,” she admits, “but they have grown on me. I plan on having the inside painted Gun Metal and the face of the spokes red in January.”
To keep the Corvette’s greenhouse cool in the hot sun of the Deep South, the window tint is as dark as allowed by Alabama law on the sides and rear, and the lightest level on the front windshield.
As much as Becca appreciates her customized Callaway, she has participated in more HPDE events from behind the wheel of her 2014 Corvette. “I have tracked at NOLA Motorsports, Barber Motorsport and NCM Motorsport tracks.” And she has even more road course attacks in mind, after she sells her restored 1975 Stingray.
I plan on purchasing a C5 Z06, mod it out, non-street legal, for the purpose of HPDEs,” she says. “I will not need to change out fluids, brake pads or tires, or worry about taping her up. Track insurance will run a lot less, so therefore I will be able to attend HPDEs a lot more often.”
Spoken like a hard-core Corvette driver—but one that really enjoys putting on some Lipstik, too!