Supercharging an engine for more power is nothing new; racers and even OEM manufacturers have been using superchargers and other forced-induction systems for years to boost the power their engines produce. In fact, before superchargers were utilized in the automotive world, airplane piston engines were equipped with superchargers to counteract the effects of thinner air at high altitudes, allowing aircraft to fly higher and more efficiently because their engines could make sea-level rated power, even up at altitude. While automotive supercharger systems may seem high-tech to the layman, in reality, a supercharger is nothing more than an air compressor that pressurizes the air going into the engine. Since more air is going through the engine, more fuel must also be added to achieve the right air/fuel mixture. The result is more power through increased cylinder pressure, and the power levels that supercharged engines can reach is nothing less than astounding.
When most of us hear the word supercharger, we envision the roots-style blower that adorns Top Fuel Hemis at NHRA events. While this style of supercharger is efficient, makes great power, and looks impressive sticking out of the hood, it just isn't practical for a car that's driven regularly on public roads. As an alternative, centrifugal-style superchargers-named for their centrifugal compressor-are smaller, very efficient, and don't have to be mounted on top of the engine, so they're a great choice for underhood applications.
When the guys at Procharger told us they'd developed a supercharger kit for the already potent Charger R/T with the 5.7 Hemi, and that rear-wheel gains of 100-plus horsepower were attainable with an engine-friendly 6 psi of boost, we had to try it out.
By now you may be thinking, Hey, if a supercharger just blows more air into the engine, I'll just duct my leaf blower into the carburetor and go racing! In reality, it's not that simple. As a function of compressing air, superchargers create heat, and that heat is transferred to the intake charge. Since a hot intake charge is counter-productive to power, the Procharger kit includes an air-to-air heat exchanger-called an intercooler-to cool the compressed air back down. Also, since a supercharger forces more air into the cylinders, more fuel must be added to keep the fuel/air mixture in the correct range. In a fuel-injected car, such as our '06 Charger R/T, adding fuel is accomplished by installing the larger injectors provided in the kit, and tuning the car's factory computer to supply more fuel with a supplied Diablo computer tuner. In addition to reprogramming the engine computer's fuel curves, the Diablo tuner also adjusts ignition timing to prevent detonation due to higher cylinder pressures. If you're thinking this is high-tech, you're right. Fortunately, the engineers at Procharger have done their research carefully, providing an easy to install kit complete with a preprogrammed Diablo tuner to make the job easy. So easy, in fact, the kit can be installed in about 8-10 hours with ordinary hand tools.
If you're a regular reader of Mopar Muscle magazine, you probably recognize the car we're working on. This car belongs to Alan Allard of AAR Quality Fiberglass, and he graciously provided it for our testing. In a previous issue, we installed an aftermarket exhaust on this Charger R/T Daytona model, as well as short-tube headers, gaining some 15 hp. Since we dyno'd the otherwise stock car after the exhaust installation, we know that it was making 255 hp and 280 lb-ft of torque at the rear wheels.
With our baseline established, we enlisted the help of Lance Johansen, Mike Carlson, and Jeff Lacina from Procharger to perform the installation. While these professionals easily had the kit installed in about a day's work, a weekend is probably a more realistic timeframe for someone installing this kit at home for the first time. Follow along as we show you how it's done, and the impressive dyno results that followed the installation.
You might be wondering why you're just seeing a Procharger system for the new Hemi Charger that's been in production for more than a year now. Rather than throwing a system together that was merely adequate, the engineering team at Procharger did what they do best. By spending extra time in the development phase, Procharger put together a kit that is complete, easy to install and maintain, and shows impressive power gains while not sacrificing engine durability or drivability.
Before the Procharger kit was ever installed in a vehicle, it was installed on a dyno engine to be tested and refined. The Procharger engineers made some 227 total engine dyno pulls on their test Hemi before deeming the system ready to install in a vehicle. Once installed in their test vehicles, the Hemi system was again tested and refined through some 192 pulls on the chassis dyno, then street and track tested extensively before being released for retail sale. While this research and development is expensive and time consuming, the end result is a supercharger system with spot-on air/fuel ratios at all engine rpms, and an all-inclusive kit that is easy to install and maintain. Additionally, drivability and power are superb, without sacrificing engine durability. It would be nice if all products we tested were as well engineered as the Procharger system for the new Dodge Charger.
