Steve Baur
Former Editor, Modified Mustangs & Fords
January 22, 2007
We were looking for street superiority and found it with ATI's P-1SC ProCharger kit. Notice the pretty Camaro before we took the hammers and cleavers to it.

For the 5.0L owner, there are a ton of ways to make easy horsepower and if we plan to hang with the current herd of Mustangs, supercharging is something we simply must do. Since MM&FF has two 5.0L naturally aspirated engine buildups completed or in the works, we looked to see how much power we could make with a blower.

Accessible Technologies, Inc. has been home to the ProCharger family of centrifugal superchargers since 1993, and is where we turned to unnaturally aspirate our Mustang GT. From boats to automobiles and motorcycles, there is a ProCharger for just about everything. Someone even used one to create a commercial airline de-icer, which works by simply blowing the ice off of the plane. Cool stuff for sure, and the diversity in which the product is used serves as additional research and development material for future versions of the ProCharger. But in our case, we simply want more power.

One of the reasons why we went with a ProCharger is because of the intercooler in its kits. When air is compressed, as in a supercharged application, the atoms bounce off of each other as they become more densely populated. This results in friction, and thus raises the temperature of the incoming air charge. ProCharger, and many turbocharged applications, use an intercooler to lower the air charge temperature by as much as 100 degrees, which in turn allows a more aggressive timing curve to be utilized in order to make additional power. Intercooled superchargers are less susceptible to powerfade, unlike non-intercooled systems. Ultimately, a cooler change means less chance of detonation and we're all about that.

Be Cool

This is about 80 percent of the ProCharger kit. We didn't have a big enough table to display all of the included components, but the meat and potatoes are here-one P-1SC head unit polished and one sheetmetal three-core intercooler. Also pictured are the fuel management unit, the inline fuel pump and relay, the blow off or surge valve, the K&N filter, the 14-pound pulley and the belts for both it and the 11-pound unit. This is a complete and well-thought out kit that includes just about everything you could think of. Prices differ from dealer to dealer but expect to pay around $3,500.

There are generally two types of commonly used intercoolers, one is the air-to-air intercooler and the other an air-to-water intercooler. The air-to-air unit features a radiator-type cooler that uses passing air to cool the contents. An air-to-water unit circulates water around the intake charge to lower the temperature. Some racers will stuff ice into the water tank for additional efficiency to super cool a water-to-air intercooler.

The ProCharger we chose for our project is the P-1SC intercooled kit that fits Ford Mustangs from '86-93. The system is good up to 825 hp and can create boost levels of up to 30 psi. Using a radial impeller for a broad torque range, the head unit is capable of delivering 30 psi of boost and, with its CARB EO #D-365, the kit is 50-state legal and has up to 14 psi of boost. A 12-month warranty is standard, with an optional two-year extension available. For those who race, the P-1SC is legal for use in NMRA Real Street without the intercooler, but ATI offers the P-1SC-2 for use in that particular class, as the helixed impeller offers more high-rpm performance.

The SC in P-1SC stands for self-contained. As most centrifugal superchargers require tapping into the engine's oil supply to lubricate the internal transmission, the SC ProChargers come with their own internal oil supply system, which saves a few steps during installation and provides a cleaner overall installation. After a 500-mile break-in period, the fluid is changed, and the next interval is 6,000 miles. The oil is a 0-weight synthetic oil specifically designed for use in the high-speed environment of a supercharger. It also runs much cooler than engine oil, which has already been heated by the motor before going into the blower. Now that we have covered the supercharger we have chosen, let's go into a little detail on the application.

Blue Mule

Our installation mule is a '90 Mustang GT equipped with a 5.0L engine and five-speed transmission. The car is well maintained, but has racked up 139,000 miles on the odometer. Modifications to the Mustang include an off-road X-pipe, Flowmaster two-chamber mufflers, a K&N filter and the "10-minute" tune-up. Baseline numbers for the filly came in at 202.2 rear-wheel horsepower and 275.6 lbs-ft of torque at the pony wheels. On the track, the GT posted a 14.45 at 96 mph and a 14.46 at 95.7 mph. Obviously, there is a better elapsed time to be had, but the 2.73 rear gear ratio is not exactly optimum for mercurial 60-foot times. We plan to remedy the ring-and-pinion situation later, but we'll need to return to the track with the supercharger and 2.73s for back-to-back comparison.

This is our stock, 139,000-mile motor. Why bolt a supercharger onto such an old motor? Well, we've seen many a 5.0L live well past 180,000 and ours ran quite well so we decided to go for it.

The ProCharger comes as a complete kit, with everything one would need to install this and head on down the road to better power and quicker elapsed times. Due to the high mileage of our engine, ATI recommended that we get a new set of fuel injectors to make sure we had equally rated injectors on all eight cylinders. After speaking with the folks at LaRocca's Performance, we opted for a set of 42-pound Ford Racing Performance Parts squirters. This was because the Mustang may see future engine modifications, thus requiring larger units. In using such large injectors right off the bat with our application, ATI recommended not using the supplied fuel management unit (FMU), as the injectors offered enough fuel for our power level, and a better idle quality would be had without using both of the items on our stock engine.

The injectors were sourced from Brothers Performance Warehouse in Corona, California. Brothers has just about any part you could want or need for your Mustang, so we gave a call for the injectors, as well as for a BBK adjustable billet fuel regulator, and a BBK in-tank 255-lph fuel pump. When going to a different flow-rated injector, it is important to have the mass air meter calibrated to the injectors. Brothers had a Pro-M Bullet 75mm meter calibrated to the 42-pound injectors and shipped it out to us.

Another fail-safe item is a good ignition system. We had recently given the Mustang a tune-up, save for spark plug wires, but seeing as the stock coil had over 100,000 miles on it, we opted to replace it with a Crane LX-92 high-performance coil. This was used with Crane's HI-6 CD ignition with rev limiter and timing retard. The HI-6 is a state-of-the-art, capacitive discharge-type ignition system that delivers up to 12 sparks to assure quick starting. Better spark is also required when cylinder pressure is increased, as in a supercharged or high-compression application.

Crane's HI-6 also comes with a staged rev limiter that can be set at up to 9,000 rpm in increments of 100 rpm. All HI-6 units can be equipped with the optional TRC-2, which is a timing retard control module. This is set with the knob on the module and retards the timing in proportion to boost levels. In keeping with the Crane ignition theme, we opted for a set of its 8.5mm Fire Wire spark plug wires. These offer a low 25 ohm-per-foot resistance and transmit up to 50 percent more energy to the spark plugs than other performance wires. The FireWires use a "reactive core" to filter out RFI and EMI noise, which keeps your radio clear and protects your computer. They also have 550-degree boots for that hot environment between the headers.

For the supercharger installation, we journeyed to Danny's Pro Performance in Keyport, New Jersey. Dan is a Mustang fanatic of the first order and putting power into the pony is something he excels at. Although there were quite a few parts to be installed, Dan was up to the task of giving us Camaro-smashing power.

During the installation, we ran into a few issues that stalled the project, but only until a remedy was easily found. Our Mustang had been equipped with a Hose Wizard R-134A retrofit air conditioning system. While it blew a frigid 38 degrees in the cockpit, the aftermarket Sanden compressor it utilized would not fit in the supplied mounting bracket. To avoid going through some major reworking we temporarily installed a factory compressor.

We had originally ordered our ProCharger with a vertical-mount, three-core intercooler but decided to change that during the installation. We liked the idea of hiding the intercooler in the front fascia, and the fact it'd be out of the way. However, it required quite a bit of trimming to both the bumper support and the headlight support that the owner did not approve of, so we simply exchanged it for a horizontally mounted unit.

These are in fact, more efficient than the front-mounted pieces, but they reside rather low to the ground. We measured 3.5 inches of clearance with the stock suspension, so if you have lowered your car, you may want to consider this. We've put over 200 miles on it since installation and the only time we scraped it was coming out of some steep driveways (we forgot it was down there). On the highway, it was subjected to some pretty good shots from our strafed and pothole-ridden New Jersey interstates, but never touched the pavement.

Those were the only two snags in an otherwise easy installation. If you're lacking in basic automotive knowledge, we suggest finding a professional like Danny's Pro Performance to perform your work. We also suggest that you have the car tuned properly with a custom-burned computer chip. For this, we went to LaRocca's Performance in Old Bridge, New Jersey.

Five-liter magnate Jimmy LaRocca and his crew of technicians have the handle on ProCharger tune-ups, so we looked to them to tweak our pony for power. LaRocca uses Autologic software that they have adapted over the years to provide the latest in tuning technology and their custom computer chip did many things for us.

For starters, Jimmy made sure that our GT maintained a safe air/fuel ratio throughout the power range. Taking into account the Mustang's high-mileage and many heat cycles throughout the years, Jimmy kept the a/f ratio to 11.5:1. He could have easily squeezed another 10-15 hp out of it, but we wanted to be on the safe side, and our horsepower gain was more than enough to put smiles on our faces. Idle quality is another thing that can be adjusted with the chip. Many factors go into tuning this equation. Things like how the throttle position is set and the type of mass air meter and injectors used are all orchestrated by the computer. One more important thing that can be adjusted with the computer chip is boost retard. We were not aware of this when we ordered the Crane timing control module, but it can be compensated for in the computer tune. With the age of the engine being the main factor, LaRocca opted to pull out four degrees of timing to ensure safe operation.

Prior to tuning, the base ignition timing was set back to 10 degrees. A few pulls were made to get the idle and air/fuel ratio set, and then LaRocca, with help from Andrew Barrale and Jimmy Chahalis, went for the power. How much did we get? Well, remember that the stock figures were 202 hp and 275 lbs-ft of torque. With the ProCharger pumping 10 psi of boost we made 333.4 hp and a stump-pulling 389.7 lb-ft of torque at the rear wheels. Now that's some LS1-smoking power in our little 3,200-pound GT. Given a drivetrain loss of 15 percent, we estimate flywheel horsepower to be around 390, and torque to be about 448 lbs-ft.

In addition to the 11-pound pulley that came with the kit, we had ATI include a smaller 14-pound pulley-hey, why not? Although a lower-mileage engine would have no problem supporting such boost, we're going to hold onto ours for a while, as we want to get some track time under our belt before we go for broke.

Speaking of the track, we had hoped to bring you some results, but unfortunately the 1320 is covered by 12 inches of snow at the current time, so you'll just have to tune-in later for elapsed times. Our '90 GT is also getting some huge Cobra brakes courtesy of Ford Racing Performance Parts and a trick set of wheels from Discount Tire, so keep your eyes peeled as this pony is blown, stock, and born to rock.