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Twin Screw Positive Displacement Supercharger

The twin screw supercharger delivers boost instantly at low rpm, which is the virtue of a positive displacement supercharger, and also compresses the air - this delivers superior efficiencies. The twin screw is the perfect supercharger for the non-hotrod person who needs extra power, performance, and safety under load or while towing, or at high altitude, that comes from extra torque and full power at low rpm. Online Games

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Twin Screw Supercharger - a positive displacement compressor

The twin screw supercharger is a positive displacement air mover, in that it moves fixed amounts of air per revolution, like the roots type blower. Unlike the roots however, which is only an air delivery system, the twin screw supercharger is also a compressor. The counter rotating lobes and chambers of the twin screw are designed for a screw-like tapering effect which runs its intake air into a smaller space for output, thus compressing it. The rotors have very close tolerances yet never touch. Compressed air is delivered into the compression environment of the intake manifold with very little leakage or energy loss.

Because of the increased mechanical efficiencies of the superior design, the output air temperatures of the twin screw positive displacement supercharger are radically improved from the roots type. The Whipple twin screw quotes adiabatic efficiency of 70%-80% range across the whole powerband.

As with the roots, since the supercharger is under continual drive, and since it delivers boost practically from idle, overboosting is prevented by the use of an intake bypass system, which allows the engine to breathe normally at cruising or idle: the bypass closes on throttle use, delivering full boost.

Full boost by 2000 rpm

The twin screw supercharger creates boost the instant the throttle is touched, and generally reaches full boost by 2000 to 2400 rpm. Full boost is then available all the way to redline. A positive displacement compressor is ideal for street performance cars or trucks and suv's, and automatic transmissions.

Vehicles used for towing remain very responsive with positive control using this type of supercharger. The instant torque for accelerating, passing, and hill-climbing diminishes the strain on the engine and increases the safety factor. The twin screw compressor is especially useful at high altitude, where physics dictates that all engines lose power, and where our American geography dictates we often take the family vehicle on vacation towing a trailer in heavy traffic.

The twin screw supercharger is essentially silent, producing discernible sound no greater than whisper strength. It has a low profile and generally requires no hood modification. Of all the forced induction systems, the twin screw compressor supercharger is the most obvious for the bootlegger's car, the sleeper, and this is timely in an age where supercharging is no longer just for speed enthusiasts, but for all drivers who have needs for extra power and performance during fairly standard driving conditions.

About Supercharging

How Forced Induction Works

Superchargers Compared

Supercharger Comparison Chart


Centrifugal Superchargers

Roots Style Supercharger

Twin Screw Supercharger

Supercharger Heat

History Of Supercharging