Best Blower For Your Mustang - Choose Your Weapon - Tech

Air-to-water intercoolers work well for short periods or when there's ample cooling time between uses, but what about sustained use? For something like the Silver State open road race where the motor is subjected to full throttle boost for as long as 30 minutes at a time, an air-to-air intercooler would be best suited. The reason for this is that the elevated speeds run in the open road race provide plenty of cooling for a front-mounted intercooler. In essence, the high speed provides all of the cooling air to maximize the efficiency of the intercooler. Such a system will still not match the efficiency of an air-to-water run with ice water, but how much ice water would you need to run flat out for 30 minutes? The answer is that you could never carry enough, so the air-to-air intercooler is the setup for lengthy high-speed events.

You should now be asking, which system is best for street use? The answer is actually that both systems work excellent on the street. In fact, despite the claims by the various manufacturers, you'd be hard pressed to determine the difference between a good air-to-air and air-to-water system running street boost levels. Both forms are used successfully by OEMs as well as the various aftermarket blower manufacturers. As is the case with blowers, choosing the best form of intercooling is more a matter of cost and complexity than overall efficiency.

Supercharger Shootout-Roots vs. Twin Screw vs. Centrifugal (11 psi)
The power curve supplied was generated by running a Roots-style blower, a twin-screw, and a centrifugal supercharger on the same motor at the same maximum boost level. The timing and air/fuel curves were also kept constant for each application. Putting these numbers into proper perspective is the fact that this 4.6 DOHC motor produced 426 hp in normally aspirated trim before installing any of the blowers. It's clear that the two positive-displacement superchargers (Roots-style and twin-screw) offered much more power in the lower rev ranges than the centrifugal.

The centrifugal offered the greatest peak power of the bunch when tested on the 4.6 Four-Valve motor, but is peak power all you're after?

Since most of your driving takes place in the lower rev ranges, the positive-displacement superchargers have plenty to offer. Even the factory Roots-style blower on the '03 Cobra motor offered plenty of average power, it just was unable to keep pace with the more efficient twin-screw design. The great thing about the twin-screw is that it makes for one heck of a blower upgrade to almost any factory force-fed Ford. Replace the Roots-style blower with a twin-screw on your Lightning, Cobra, or GT500, and you're looking at some serious power potential. Regardless of which one you choose for your application, supercharging your Stang will result in some serious power.