In the few short years that the sixth-generation Camaro SS has been on the street, enthusiasts have quickly come to realize just how well it responds to performance tweaks. With the LT1 dishing out 455 horsepower right out of the box, in naturally-aspirated form, it serves as an excellent starting point for modification. Throwing a bit of boost into the mix sees the output quickly climb into LT4 power territory (and beyond) with very little fuss to get there.
What’s more, with strong aftermarket support for not only the LT series motors, but the sixth-generation Camaro specifically, owners of Chevy’s newest pony car have numerous options in terms of how to dial in their forced induction setup for maximum efficiency for a particular application, and that includes their intercooler strategy.
Generally speaking, air-to-air intercoolers serve as the default configuration for most street and strip setups. Provided there’s a proper air flow path for the intercooler to use, air-to-air setups have a number of advantages to their design for street driven vehicles, including their relative simplicity, light weight, lack of additional power requirements for its components and, with no fluid involved, there’s no potential for leaks.
However, air-to-water intercoolers have advantages of their own, and in some applications, their use is essentially required if you’re looking to get optimal efficiency from your boosted motor, especially when you’re making big numbers on the dyno. We sat down with the folks at ProCharger to go over the finer points of their new air-to-water intercooler kit for the sixth-generation Camaro SS to get a better understanding of the applications it’s best suited for, and then headed over to Cunningham Motorsports, bolted the system up to the Camaro in question along with a few other performance tweaks, then rolled it onto the dyno to see how everything shook out.
Last year we installed a ProCharger supercharger with an air-to-air intercooler on Cunningham Motorsports’ test mule, which we detailed here. While that woke up this bolt-on sixth-generation Camaro significantly, the power it made still falls within ProCharger’s recommended power range for an air-to-air intercooler system. However, Cunningham Motorsports has big plans for this car in the future, and in preparation for future modifications to come we’re swapping it over to an air-to-water setup and making a few additional tweaks while we’ve got it in the shop.
When To Go Air-To-Water
“Two key factors lead us to develop an air-to-water intercooler system to expand our impressive air-t0-air line up,” says ProCharger’s Erik Radzins. “First, in recent years, half-mile and mile-racing has gained in popularity. With this form of racing comes very high speeds where aerodynamics at the front of the car play a large factor. We found that at these highly elevated ground speeds, sometimes air just doesn’t want to go through a thick intercooler core. This was solved by the air-to-water unit and heat exchanger.
Secondly, space is a factor on these modern cars. The engine bays keep getting tighter and even though we have air-to-air intercoolers our customers have used up to 1,600 hp, not all cars (like this Camaro) can easily fit that behind the factory bumper and grille.”
The simplicity of air-to-air intercooler setups makes them a go-to choice for most forced induction applications. But while this design usually works well for quarter mile drag strip runs, the increasing popularity of half-mile racing has revealed that the higher speeds involved tend to hamper airflow through the engine bay rather than help it. In turn, air-to-air intercoolers aren't functioning efficiently at those speeds. However, with the additional plumbing, wiring and pump involved, switching from an air-to-air system to an air-to-water setup isn't as simple as swapping out one component for another. Accordingly, with the demand for air-to-water intercoolers on the rise, ProCharger has taken much of the guesswork out of the equation by developing a kit for the sixth-generation Camaro that makes the upgrade a straight-forward proposition.
Radzins went on to tell us that beyond the aerodynamic constraints of a particular application, packaging can also become an issue when big power is the goal. “We have air-to-air intercoolers that will work at up to 1,600 horsepower,” he explains. “But anything that is, say, four-digits at the wheels and above, such a large air-to-air system is required that you really have to start cutting the car up to make it fit. We can use an air-to-water intercooler to accomplish the same goal in a much smaller package and avoid having to chop up the car to get it in there.”
Every think you see here will be going away, replaced by the air-to-water intercooler kit which includes a heat exchanger, intercooler, water pump, coolant reservoir, water pump, tubing, relays, and plumbing to get the job done.
The pull started off around 80 degrees and by the end of it we were seeing around 115. That was just water, no ice, and as soon as we got out of it the temperatures came right back down.–Ryne Cunningham, Cunningham Motorsports
“Another major benefit to our air-to-water intercooler system compared to those commonly found in the engine bay, is heat,” Radzins continued. “Our entire system (intercooler, pumps, heat exchanger, and reservoir) are mounted in the front bumper, in front of the radiator and engine bay.This location was chosen to minimize heat transfer and maximize performance.”
But Radzins is also quick to point out that air-to-water intercoolers remain the best choice for specific applications rather than serving as the obligatory selection for any boosted setup. “The market for this air-to-water system is really aimed toward these half-mile racers and guys who’re making four-digit power,” he explains. “There really isn’t a need for it at power levels and speeds below that, and air-to-air intercoolers have their own benefits for normal applications – there’s just very little to worry about with no moving parts involved.”
For street driven cars that make under 1,000 rwhp and don’t compete in half-mile racing, an air-to-water intercooler setup might be overkill, according to ProCharger. But as air speeds increase to the levels seen in half-mile racing, a car’s aerodynamics and overall shape play a greater role in the ability for air to flow through the engine bay rather than pushing over and under the car, creating situations where a mechanically driven air-to-water setup will likely prove more efficient and yield better results.
Regardless of whether the system you are using is an air-to-air or air-to-water, Radzins tells us that countless hours of research and development have gone into ensuring each kit performs at peak efficiency. “Before ‘on car system testing’ was ever started, loads of engineering hours were spent doing testing on each individual component in the intercooler system,” Radzins explains. “For example, we tested just about every single water pump we could get our hands on. From hardcore race parts, to OEM offerings.Once each item was vetted, we could then move to be tested in the complete system form. This level of detail in testing is what helped lead to a neat and tidy package that performs amazing, and has durability to last.”
But with 1,000 horsepower builds becoming more and more commonplace every day, these air-to-water intercoolers will inevitably become an increasingly popular option for builders looking to maximize the potential of their setup. Our sixth-gen Camaro SS install candidate for this retrofit serves as further evidence of this, as its output continues to ramp up toward that realm after a small series of modifications.
Once we wheeled the Camaro into the shop at Cunningham Motorsport, got it on a lift and yanked the front wheels off, it was time to get to work. First, the inner fender wells need to be removed.
Removing the inner fender wells provides access to the charge pipe and auxiliary coolers. It also allows for the removal of the front fascia, which we'll need to take off in order to swap out the old intercooler system for this new kit.
With the fascia removed we now had access to the air-to-air intercooler that we were swapping out. The bumper support would also need to be removed in order to access the intercooler brackets, which are sandwiched between the support and the chassis.
After unhooking the Big Red Race Valve and removing the air-to-air intercooler, both are set aside as neither will be reused with the new system. The auxiliary cooler is also moved out of the way.
The driver’s side headlight is the next item to go, as is its support bracket. This allows space for a new charge pipe to snake its way through to the front of the car. Don’t worry, it’s going back on the car later. After removing the charge pipe from both the throttle body and the supercharger head unit, we’re ready to start making some upgrades.
With the mounting brackets now attached, the air-to-water intercooler main reservoir is ready to be installed in the car. To provide room for the new system, the fan shroud also needs to be trimmed down a bit.
Installation starts by mounting the filler reservoir (the smaller of the two tanks) to the radiator support on the passenger side.
The filler reservoir is mounted to the passenger side of the radiator support. The reservoir hose passes through the headlight bucket.
To make room for the new charge piping, some trimming to the headlight mount bracket support on the drivers side also needs to be done. This will make room for a new headlight mount bracket, which is provided by ProCharger, for the upgrade.
The stock support must be tweaked to create room for the installation of ProCharger's headlight mount bracket. This in turn provides clearance for the new charge piping of the air to water system. You may also want to paint the exposed metal from the trimming process to prevent corrosion, as we did here.
Continuing on, the factory driver’s side auxiliary cooler must be drained and removed, as it cannot be retained with the new kit. However, ProCharger assures us that its removal does not create any cooling issues.
The trans cooler mount also needs some modification in order to allow clearance for the new charge piping and heat exchangers. The upper tabs are trimmed off to make way for the new brackets we're using.
The new heat exchanger goes on next. Like the one utilized with the air-to-air system, this will be mounted in front of the factory radiator. ProCharger provides the necessary brackets in order to properly mount the exchanger included in the air-to-water kit. Once the new heat exchanger is mounted up, the main reservoir, intercooler, and water pump can be installed and plumbed into the heat exchanger.
With the new air-to-water setup plumbed, we filled the system with Dex-Cool antifreeze. From here we turned our attention to the wiring that controls the system’s water pump.
Next we wired up the activation relay for the water pump. The pump's relay lead is then hooked up to the fuse block. With that taken care of, we turned our attention to the installation of the vacuum pump relocating bracket, which is installed as shown on the right.
We took this opportunity to upgrade the supercharger head unit as well, replacing the ProCharger P-1SC-1 unit with a F1A-94.
Since this Camaro already had a ProCharger P-1SC-1 supercharger kit installed in it when it rolled into the shop, swapping over to the F1A-94 head unit was a pretty straight-forward proposition.
This head unit features a custom designed 7075 billet aluminum impeller and a CNC machined transmission case. Rated at up to 1,200 horsepower, the F1A-94 offers a maximum airflow of 1,625 cfm and maximum boost of 38 psi.
With the new head unit installed, we turned our attention to the charge piping.
This under hood bracket must be removed in order to provide room for the charge piping. With the charge piping sorted, the factory vacuum pump is relocated and installed as shown in the image on the lower right.
With the lion’s share of the installation now completed, we were in the home stretch. In order to maximize airflow to the new heat exchanger, the front bumper’s foam insert was removed. Getting it out can be accomplished with just a pry bar, as it is attached to the bumper using double sided tape.
Once the bumper's foam insert was removed in order to direct more air at the new heat exchanger, the charge pipes were installed on the car. From here it's simply a matter of buttoning up the car by reinstalling the front fascia and then checking to ensure that everything is functioning as intended before we go find out what kind of power gains these modifications have given us.
With everything buttoned up, we headed back to the dyno to see how the Camaro’s LT1 responded to the various tweaks made. When the car rolled into the shop, its list of modifications included the ProCharger P-1SC-1 supercharger kit with an air-to-air intercooler, Kooks headers, and an exhaust system, but the rest of the powertrain was otherwise as it left the factory.
The baseline chart on the left shows the power that the LT1 was making when it rolled into the shop, figures that are generated by an LT1 with stock internals and supplemented by a ProCharger P-1SC-1 supercharger, Kooks headers, and an aftermarket exhaust. While the swap to the air-to-water system was being made, Cunningham Motorsports took the opportunity to swap over to a F1A-94 supercharger head unit as well as one of Cunningham Motorsports' custom ground camshafts. The chart on the right shows the net result of these modifications with the air-to-water intercooler system installed.
An air-to-air setup will gain temperature through each gear as you’re going down the quarter mile. With an air-to-water setup like this, it will come up initially and level off for the rest of the pass. So the gain you see in first gear is likely where it will stay for the whole run. – Erik Radzins, ProCharger
Along with the change over to ProCharger’s new air-to-water intercooler system, Cunningham Motorsports also installed a new custom ground camshaft (the specs of which they have opted to keep on the down-low), along with the aforementioned swap from the P-1SC-1 head unit over to ProCharger’s F1A-94 unit.
As evidenced by the dyno chart comparisons above, the modifications not only woke the motor up quite a bit, they also changed the power curve substantially as well, with the motor now continuing to build power all the way up to the 7,000 rpm cutoff.
The changes resulted in an increase from 565.88 horsepower and 497.23 lb-ft of torque with the previous setup to 853.26 horsepower and 644.67 lb-ft of torque – a gain of 287.38 horsepower and 147.44 lb-ft of torque respectively. However, this was accomplished using 14.5 pounds of boost compared to the old setup’s 7.8 psi, as well as the change in camshaft and head unit. While we’re aware that this is somewhat of an apples to oranges comparison, it does demonstrate what kind of power the air-to-water intercooler is capable of supporting.
It also demonstrates just how cool the air-to-water intercooler is keeping the intake charge. Radzins tells us that ProCharger has conducted extensive research with the system, and even they were surprised by the results.
“IATs, even on one of the hottest days we’ve ever had here, at the track they never went over 122 degrees,” Radzins explained. “And during the quarter-mile testing, it never saw temperatures higher than 108. Even then, as soon as you let off the gas, the temperature would drop clear back down; I was really impressed. It has such a huge reservoir on board it can just recover so quickly.”
Ryne Cunningham, owner and head tuner at Cunningham Motorsports, said he was saw the same thing while we had the car strapped down on the dyno.
“The pull started off around 80 degrees and by the end of it we were seeing around 115,” Ryne said. “That was with just water, no ice, and as soon as we got out of it the temperatures came right back down.”
While the motor is still under Radzins’ suggested power for an air-to-water system, it’s well on its way to four-digit horsepower numbers at the wheels, and making this swap now ensures that the intercooler system will be ready for it when the motor gets there.
Here you can see the coolant reservoir and intercooler sitting behind the bumper cover.
The benefits of the air-to-water system aren’t solely constrained to the sixth-gen Camaro either. ProCharger is now offering air-to-water intercooler kits for the 2017+ Camaro ZL1, 2014+ Corvette Stingray, and 2015+ Corvette Z06 as well. So no matter what kind of GM iron you’re rolling, ProCharger can help keep it as cool as posible.
Find yourself in a similar situation with your LT1-powered sixth-generation Camaro, or the other GM platforms listed? Give the folks at ProCharger a buzz and get your intercooler game straight for big power and half-mile or mile drag racing with an air-to-water kit. The results speak for themselves.