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 we heard Procharger had...

When we heard Procharger had an intercooled supercharger kit for the new Hemi-equipped Charger, Magnum, and 300, and that big power gains could be had with about a day's worth of work, we had to try it out. Follow along as we install a Procharger supercharger on the new 5.7 Hemi for amazing power.

In a previous issue, we installed...

In a previous issue, we installed an aftermarket exhaust on our project Charger. After the installation, the car made 255 rear-wheel horsepower on our Mustang dyno; we're hoping for a significant increase after the Procharger installation.

We begin the installation...

We begin the installation by removing the engine cover and air dams from the front of the car. While a lift isn't necessary, it makes accessing the underside of the car much easier.
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.

The lower air dam is removed...

The lower air dam is removed from under the car. This installation can be made a little easier by removing the front bumper fascia, but it isn't necessary. We decided to perform the work with the fascia in place.

The inner-fender splash shields...

The inner-fender splash shields don't need to be completely removed, but loosening them from the forward fenders allows more room to work.

Since the supercharger sits...

Since the supercharger sits right where the factory airbox is mounted, the airbox has to come 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.

The grille also needs to be...

The grille also needs to be removed to access the power steering cooler and to install the intercooler.

Now that we have the car prepped,...

Now that we have the car prepped, it's time to open up the boxes and check out the Procharger kit. This is obviously a well-designed system; they even include tie-wraps to secure wiring that is rerouted during the installation.

The intercooler brackets are...

The intercooler brackets are installed on the forward side of the radiator to existing holes in the radiator support. One of the great features about this kit is that no drilling or fabrication is needed; the parts simply bolt in.

The intercooler can now be...

The intercooler can now be mounted to the brackets on the front side of the radiator. Though space is tight, Procharger optimized the design of the intercooler to make it as efficient as possible.

With the intercooler installed,...

With the intercooler installed, we move to the back side of the radiator where the electric cooling fans must be removed, allowing access to install the crank pulley that will drive our supercharger. A nice feature of this kit is that the radiator and hoses stay in-place, so there's no coolant mess to clean up.

Installing the crank pulley...

Installing the crank pulley is a two-person job. One holds the flywheel, and the other installs the crank pulley and torques it to spec. The drive pulley is an eight-rib serpentine unit, which easily handles spinning the supercharger.

After reinstalling the cooling...

After reinstalling the cooling fans, the power steering line can be relocated for crank pulley clearance. The power steering cooler is also relocated slightly for intercooler clearance. Again, all the necessary hardware and brackets are included in the kit.

Now the supercharger mounting...

Now the supercharger mounting bracket can be attached to the engine. This is a nice piece made from billet aluminum and polished to a high luster.

To clear the supercharger...

To clear the supercharger and its mounting hardware, the power steering pressure line from the pump needs to be clocked differently. Procharger includes this ingenious bracket to hold the factory power-steering line in its new position.

Since the supercharger sits...

Since the supercharger sits where the factory airbox used to be, this inlet tube relocates the air filter to the area in front of the driver-side front wheel. Due to space restraints, it's much easier to install the inlet tube before installing the supercharger.

Since space is so tight, the...

Since space is so tight, the supercharger is actually driven by a cogged belt on the rear of the mounting bracket. This belt is driven by the eight-rib serpentine belt we installed earlier through a jack-shaft.

To prevent over-boosting the...

To prevent over-boosting the engine when the throttle is closed suddenly, a pressure relief, or "blow-off" valve, is installed inside the driver-side bumper.