Installing A RoushCharger On A 2004 F-150

Leave it to gearheads to take an industrial product and utilize it to make more power in an automotive environment. It's happened more times than we can count, but one of the most famous applications is the Roots-style blower. Originally designed for moving air in blast furnaces in the late 1800s, the Roots-style blower was used for decades as an air movement tool for large factories. Even some civil defense air sirens used the Roots-style blower to move air to the horn. Later, the Roots-style blower was used on two-stroke diesels. Since there's no intake stroke to these engines, something was needed to force air into the engine. It wasn't uncommon to see a two-stroke diesel with a Roots-style blower for intake air and a turbo for a power increase.

The most recognizable Roots-style blower in the automotive performance world is the GM and the derivatives of it-the popular 6-71 and 8-71 have been used in hot rodding, drag racing, and diesels for decades. These Roots-style blowers were made famous for sticking out of hoods in the Pro Street days of the '70s. Later, the Roots-style blower saw more factory use in GM cars powered by the supercharged 3800 V-6 (Bonneville SSEI, for example) and their more recent Ecotec four-cylinder. Ford has used the Roots-style supercharger for years, first in the '89 Thunderbird Super Coupe, and more successfully in the '03/'04 Mustang SVT Cobra "Terminator." And let's not forget that the highly popular and baddest high-performance truck-the Gen 2 Lightning-featured a Roots -style blower. Now Roots-style blowers have come full circle with aftermarket kits available for popular applications such as the Mustang and F-150.

The complete intercooled RoushCharger kit is shown here, sans a few bolts and clamps. All you'll need for installation is a well-stocked toolbox, a 50/50 mix of coolant for the intercooler system, and a nice weekend with a friend or two.

But why a Roots-style blower when all your drag racing buddies swear by their centrifugal units? That's simple; it's all in the application. Racers use centrifugals (also originally designed for simple air movement) because they make their boost at high rpm, where a drag racer's always at in the power band. The Roots design is a positive displacement blower; meaning it moves a lot of air at low rpm. That low rpm operating range is perfect for street use and is very desirable for towing applications (which, again, is why the Roots was so popular with the diesel trucks). Peak torque is made at a very low rpm, almost off idle in some applications-perfect for pulling that trailer with your race car or show vehicle on it. The torque curve is also long and flat, which aids acceleration when you have a trailer hanging off the back bumper.

Merv Rego, who owns a restoration and custom shop, along with his wife, Pat, traded up from a 460-powered dualie to the '04 F-150 Lariat seen on the previous page. Not only was the new generation F-series a huge leap from Merv's old dualie in interior luxury, fit, finish, and fuel economy, but the 5.4 Three-Valve power plant was a whole new experience after owning a big-block and pushrods for over 10 years. After towing a few customers' cars with their open-deck steel trailer, the one flaw in the F-series stuck out like a red-head in Harlem. "This thing needs a blower for towing," Merv tells us. A call to Roush Performance for their newest F-series offering, its intercooled RoushCharger, certainly fixed Merv's towing issues, and will for you too. While Roush Performance recommends professional installation, especially for warranty continuation, we wanted to see just what was involved with the installation and opted to tackle it ourselves. So follow along as we hit the highlights of the installation and decide for yourself.

The Goods

Requires 91-octane or better fuel

Unlike the very popular '03 Cobra "Terminator" Eaton-based supercharger, the Roush kit utilizes a top feed inlet versus the Eaton's rear feed.	The exit location for the compressed air is very similar on the bottom of the blower.	The included "Fuel Charging Assembly" (or intake manifold as we usually call them), is a real work of art and what allows the whole system to easily bolt to the top of your 5.4 Three-Valve with ease. Designed to reuse your stock fuel rails, gaskets, and coolant bridge, the manifold comes fully assembled with the intercooler core ready for installation with new intake manifold retaining bolts.
One of the many things the RoushCharger has going for it is a complete factory-level flash of the ECM as part of the kit. The tune itself is a closely guarded secret, requiring you to ship the ECM back to Roush for the flash tune. We've read of some tuners "looking" at the calibration and finding it almost too good to mess with, meaning Roush did their homework and the tune will be spot-on for the blower install. Don't forget to disconnect the battery before starting on the tear down. We recommend removing the ECM and shipping it out first so by the time you're done with the install the ECM will be back from Roush.	Getting underway with the tear down, the induction parts are the first to get man-handled. There are several PCV and emissions hoses you'll have to deal with that have these funky latches on them. Simply push them with a fingernail or small screwdriver. Others have a lock that needs to be popped open first.	With the induction hose out of the way, the air filter box is next. Four bolts hold it to the top of the OE plastic intake. Don't forget to disconnect the electrical connector for the mass-air meter on the driver-side of the airbox. None of these parts will be reused except for the mass-air meter itself, which gets transferred to the new inlet tube, so pack 'em up for storage or sell 'em off.
The factory throttle body, with drive-by wire, will be reused on the RoushCharger installation (both intercooled and non-intercooled kits). The throttle body is mounted in a vertical plane on the OE intake. The new RoushCharger kit will have it mounted horizontally. Disconnect the TP (throttle position) sensor and ETC (electronic throttle control) connectors before removing the throttle body from the OE intake and then quickly transfer the O-ring gasket to the new Roush Throttle Spacer to prevent O-ring growth.	One of the few specialty tools you'll need for the job will be some sort of fan wrench. In a nutshell, the fan is threaded with a left-hand thread-fan clutch instead of bolted on. You'll need to secure the water pump pulley with the tool and then loosen the fan clutch with the other half of the tool. Some people get away with a large set of Channellock pliers on the water pump pulley retaining bolts, too. Be careful to not let the fan fall into the radiator. Once the fan is loose, remove the radiator shroud and fan together.	Using a breaker bar, pull back on the belt tensioner and remove the serpentine belt from the alternator pulley (it can stay in place on the rest of the accessories). Remove the alternator top mounting bolts and its electrical connections, and then loosen the two lower mounting bolts to free the alternator. Later in the instructions you'll have to remove the battery cable adapter lug (the green plastic part in the photo). You'll also notice we've drained the coolant and removed the upper radiator hose and support bracket in this photo.

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