Going forced induction? Your max boost is only limited by your checkbook.
So what kind of monstrosity currently holds the title of national champion in the CAM-C class, where the late-model pony cars roam? A mildly modified Camaro.
It’s powered by a turbocharged four-cylinder engine, the same one found in the base model. Other than that, it checks all the boxes for CAM-C: 200-treadwear tires, a 3250-pound minimum weight, and a post-1989 build date. And yes, the car came by its championship win rather convincingly. Really.
This Camaro recently won a national championship, but it's not the top-spec, 650-horsepower ZL1 model. While it sports a few improvements, it's still powered by the four-cylinder engine found in the base car.
Let’s Autocross
In 2017, just a couple of years after several General Motors employees formed the GM Performance Driving Team, the group set its sights on dominating CAM-C with a new Camaro SS 1LE. It did just that. Team driver Shaun Bailey, a General Motors vehicle performance engineer, landed that SCCA championship by half a second. The rest of the 53-driver class contained almost every Camaro and Mustang variant offered in the past 20 years.
With its first mission accomplished, the GM crew concocted a follow-up plan to build up another V8 Camaro for 2018. A supplier issue delayed the effort, however. “At the time of this writing,” Shaun adds, “we’re still twiddling our thumbs in anticipation of delivery of those unique parts. And yes, I’m being vague about the parts, because it’s a secret.”
While they were waiting around, team members took a fresh look at the rest of the Camaro lineup. The enthusiast world tends to focus on the V8-powered models, but the team wondered if the turbocharged, four-cylinder Camaro could work. After all, the CAM rules don’t require an eight-cylinder engine.
One advantage of the four-cylinder car: It weighs about 300 pounds less than the V8-powered Camaro SS.
This simple fact puts a nearly stock Camaro Turbo within 100 pounds of the class minimum.
“The CAM-C Turbo 1LE build could best be described as organic,” Shaun explains. “It started as a gift from the Camaro development team. When we realized our V8 car plans were being delayed, we hatched the idea of building up the Turbo 1LE. The idea was formulated in May, and we started putting the car together in June.” A step-by-step development followed. “First we drove the car stock as a Turbo 1LE at a local event held at Michigan International Speedway, complete with stock wheels and tires,” he recalls. “For the next event in Oscoda, we put on the ZL1 1LE suspension, wheels and rear bar.”
Fine-Tuning the Plan
“The takeaway from that event was, suspension worked but throttle response of the 2.0T was a challenge to overcome,” Shaun says. “And this is where the team is fortunate to have so many talented and capable engineers. Matt Bush and Dave Schmitt stepped up and said they’d try to calibrate a performance tune. Things escalated quickly from here.”
Their goals were twofold: Increase boost while adding anti-lag. Sympathy for the mechanicals wasn’t a high priority. “This is a race car part,” Shaun told us of the tune. “It’s mean to the turbo.”
The anti-lag delivers 10–15 psi of boost off throttle. At corner exit, this setup delivers more torque than the team’s Camaro SS. Along with that extra power comes extra heat, though: The Camaro quickly went through three turbochargers, including one that died soon after the car returned from the CAM Challenge event in Peru, Indiana. “At this point the tune was for pump gas, and it turns out that running anti-lag on the highway for 500 miles is a good way to cook your turbo,” Shaun notes. “Thankfully it didn’t die until we drove back.”
Before the turbo let go, though, the Camaro delivered impressively in Peru. Alexander Doss, another GM team hot-shoe, finished first against the class’s 58 other drivers. Shaun took second.
The next key to more power was a cold-air intake, as the team’s original setup grabbed hot air from the engine bay. “We built a new intake before Nationals that draws cold air from the lower-left front corner of the grille,” Shaun explains. “We did have some serious concern in the rain for it becoming a straw.”
While the GM Performance Driving Team developed the performance tune now available for the eLSD found in the Camaro SS 1LE, this car wasn’t running it. Instead, it retains the stock mechanical limited-slip differential. “It is a huge tear-up to get it in,” Shaun says of the eLSD. “We’ve looked into it.”
Before Nationals, Matt and Dave tuned the car for alcohol–a 55 percent mix is their current cocktail. “We’d like to get to E85, but that will require us to solve a fuel-flow problem,” Shaun says. “We need a bigger pump in the fuel tank. This winter we’ll probably get a pump from a ZL1 installed, and then retune. This should improve robustness of the calibration, but not really solve the problem of cooking the turbo during anti-lag operation.”
The tune and a few other small tweaks netted a sizable performance increase. Chevrolet rates the stock Camaro Turbo at 275 horsepower and 295 lb.-ft. of torque. At this fall’s Tire Rack SCCA Solo Nationals, the team told us that the engine makes about 100 more horsepower than stock and another 100 lb.-ft. of torque.
“In the wet, it was impossible to drive,” Shaun adds, explaining that he had plenty of power for the monsoon-like conditions. Impossible doesn’t mean slow, however. Shaun took the national title by 1.235 seconds. Codriver Alexander Doss finished third. Once again, the class was dominated by traditional, V8-powered pony cars.
One of the car's big hardware upgrades came right from the Chevrolet Performance catalog: The damper package found on the ZL1 LE is sold separately, although Chevrolet Performance stresses that technically it's only street-certified for the Camaro SS. The exhaust and oil catch can are both custom items. Engine internals are completely stock.
So, want boost?