Obviously, the extra airflow provided by the blower must be accompanied by additional fuel, so Vortech included a rising-rate fuel regulator better known as an FMU. Not ideal for high-boost or modified motors, the FMU can, and has, worked well on blowers installed on stock applications. The author ran one in his '88 5.0L LX, while participating in the Silver State Classic open-road race. The fuel pressure gauge was pegged at over 100 psi, but the combination ran flawlessly for over 90 miles, and to this day may still be the only Mustang to have ever won the race outright. In terms of boost, the kit was supplied with a six-rib, 3.33-inch blower pulley and a 6.00-inch crank pulley. This combination netted a peak boost pressure of 6.1 psi on our stock motor.
The test mule was completely stock internally, but configured with no accessories, and it had a Meziere electric water pump and a set of Hooker 1-3/4-inch Super Comp headers feeding 18-inch collector extensions.
Since we were running the Fast XFI engine management system, we elected not to run the FMU and instead installed a set of 36-lb/hr injectors. Since the Fast XFI is a speed-density system, it wasn't necessary to run an MAF.
Prior to the installation of the Vortech, we ran the motor normally aspirated to establish a baseline. With the impressive power outputs of the modern modular motors, it's easy to forget that the original 5.0L fuelie Ford was rated at just 225 hp (a far cry from the 444 hp offered by the new Boss) with virtually the same displacement. Run on the engine dyno at Westech, the stock 5.0L produced 252 hp at 5,100 rpm and 306 lb-ft of torque at 3,800 rpm. Hardly the high-rpm screamer, the 5.0L is plenty torquey and offers a platform that responds well to performance upgrades.
Now it was time for some boost. We installed the Vortech onto the awaiting 5.0L test motor. The blower came properly oriented, so all we had to do was bolt the mounting bracket to the passenger-side cylinder head and bolt the blower in place. Next came the blower-belt tensioner, followed by the six-rib crank pulley and blower belt. We installed the silicone couplers onto the throttle body and discharge tube, then positioned the tube in place and tightened the clamps.
We liked that the self-contained V3 SCi supercharger eliminated the need to drill and tap the oil pan. It was necessary for us to space the crank and blower pulleys out to clear our Meziere electric water pump, but once tuned to perfection, the supercharged 5.0L produced 331 hp and 368 lb-ft of torque. We know in these days of 1,000hp buildup that 331 hp doesn't sound like a lot, but remember the power output of the supercharged combination is a function of the boost and normally aspirated power output. Since the V3 will support over 725 hp, all it takes is more motor and more boost.
Future-Fast Charge Cooler Upgrade
In addition to the budget boost, the Vortech supercharger kit also offered something we refer to as future-fast. Future-fast is the ability to upgrade the system in the future as finances allow. Since the power output of the supercharged motor is a function of the normally aspirated power output multiplied by the boost pressure, we can further increase the power output of the combination by either upgrading the motor or increasing the boost.
Increased boost is a simple (and inexpensive) matter of a pulley swap, as either increasing the size of crank pulley or decreasing the size of the blower pulley will increase the airflow (and boost pressure) to the motor. The result of the increased boost is more power. The downside of the increased boost is elevated charge temperatures, as the inlet temperature rises with boost. To cure the inevitable increase in charge temperature, we elected to install an air-to-water Maxflow Power Cooler from Vortech Engineering. Though nearly as expensive as the supercharger kit itself, the Power Cooler is a natural upgrade when you go looking for additional power and boost pressure--especially for street use.
4 Naturally, the Vortech...
4 Naturally, the Vortech kit included the mounting bracket assembly designed to bolt the supercharger to the 5.0L engine. Not only did the bracket attach the blower to the cylinder head, but it also worked with the existing accessories.
5 The fuel management system...
5 The fuel management system supplied with the low-boost blower kit was a simple FMU. The rising-rate regulator was designed to be installed on the return line of the factory fuel system and work with the stock 19-pound injectors. Under boost, the FMU raised the fuel pressure to supply the additional fuel required to support the additional power level.
6 Though labeled a low-buck...
6 Though labeled a low-buck kit, it was surprisingly complete, with everything necessary to complete the installation including a new mount for the factory belt tensioner and revised upper radiator hose.