The Truth About Forced Induction & The Whipple Generation II Supercharger

March 24, 2008 3:07 pm

Steeda Autosports is proud to announce the availability of the Whipple Gen II Supercharger system. When combined with the all new and industry leading Steeda Adaptive Performance Calibration the result is the BEST performance powertrain available for Ford performance enthusiasts today – period! With maximum performance and unbelievable drivability at all RPMs and under all conditions – other forced induction alternatives do not even come close to matching their combined performance output.

Whipple Superchargers

In essence, you have the best of both worlds with the most advanced and efficient forced induction system mated with the most advanced and industry leading powertrain control software and calibration available.

The Facts

Supercharging of internal combustion engines has been used for many years as a method of improving engine performance and efficiency. However, with the continued decrease in emission standard regulations and a corresponding increase in corporate average fuel economy (CAFÉ), the trend will force automotive manufacturers to down-size engines and vehicles.

On the contrary, overall torque and horsepower trends are still expected to simultaneously increase in order to satisfy customer expectations as performance orientated consumers will always want more power and performance.

From a performance perspective an excellent way to meet customer expectations is by forced induction through the application of supercharger technology. Essentially, supercharging raises both the torque and horsepower of an engine by raising the intake charge density above atmospheric pressures (Boosting) starting at engine speeds as low as idle. Furthermore, significant performance increases are realized with very compact packaging without adversely affecting the integrity of today’s low emission exhaust after treatment systems.

Generally, there are four basic types of forced induction common for the Ford performance enthusiast today each with its own specific attributes and characteristics.


  • Turbochargers
  • Mechanically Driven Superchargers
    • Twin-Screw (Whipple)
    • Roots
    • Centrifugal Supercharger

Following is a chart that depicts the advantages/disadvantages of each of the various forced induction methods in a non-biased format.

Comparison of Methods of Forced Induction
Gen II
Centrifugal Turbo Roots
Throttle Response Awesome Idle-To-Redline RPM Power. No Lag. Poor Low-Speed Response, Similar To ‘Turbo Lag’. Power Low-Speed Response. Turbo Lag. Good Low To Mid Range Power.
Driveability Incresed Lugging Ability In Higher Gears. Increased Power Throughout RPM Range. Must Downshift To Maintain Boost Level. Must Downshift To Maintain Boost Level. Increased Lugging Ability In Higher Gears.
Engine Torque Curve Virtually Flat Curve; Ideal Characteristic. Often Worse Than Uncharged Engine At Low Speeds. Often Worse Than Uncharged Engine At Low Speeds. Wide Range; Fall-Off Can Occur At High Speeds.
Heat Buildup Low; Intercoolers Not Needed – But Recommended Low; Intercoolers Not Needed – But Recommended High; Intercooler Needed High; Limits Boost Available – Intercooler Needed
Noise Very Low Noise Levels. Typically Very Noisy. Medium Noise Levels. Typically Very Noisy.
Adiabatic Efficiency 75-85% 60-78% 60-75% Peak 40-55%

Although the Twin Screw and Roots are both “positive displacement” superchargers the similarities end here. Size for size, the Twin Screw is simply more efficient even at modest boost levels. But, at high boost levels the Twin Screw technology simply vanquishes Roots designed superchargers. If you set aside the rhetoric and advertising claims, what really matters most is how EFFICIENT the supercharger is, its upper power potential, and the related torque power curve.

While the turbocharger creates great peak horsepower, turbo lag and high cold start emissions due to the increased thermal mass are significant turbocharger technology short falls. Overall, the new Whipple Gen II twin-screw supercharger delivers instant boost at all engine speeds and at a much superior overall efficiency of a Roots, Turbo, or Centrifugal design of forced induction.

What is a screw compressor and how does it work?

A screw compressor is a positive displacement machine that uses a pair of intermeshing rotors to produce compression. The rotors are essentially comprised of helical lobes that are affixed to a front and rear shaft. One rotor referred to as the male rotor will typically have three lobes. On the contrary, the other rotor referred to as the female rotor will typically have five valleys machined into it that match the curvature of the male lobes. However, the number of lobes on the male and the number of valleys on the female rotor can vary between compressor manufacturers. Nevertheless, the rotors never make contact with each other or the rotor housing, instead they are timed by a pair of gears operating in a lubricated chamber which is separated from the rotor chamber. With the 3-5 rotor combination, the male rotor turns 3 times for every one time of the female rotor. Hence, because of the number of male lobes there are three air compression cycles for every revolution of the male rotor.

Whipple Gen II Twin-Screw Operating Principals

Inlet Phase – The male and female rotors rotate counter to each other. As the lobes of each rotor travel past each inlet port at the rear entrance of the supercharger, air is trapped between consecutive lobes and the cylindrical casing. The air moves axially (forward) throughout the case and fill the inner-lobe space between adjacent lobes.

Compression Phase – As the rotors mesh, the air is trapped between the rotors and the casing. Continued rotation progressively reduces the volume occupied by the air resulting in an extremely efficient controlled compression.

Discharge Phase – Compression continues until the inner-lobe space becomes exposed to the outlet port, through which the air is discharged into the manifold.

The compression sequence continues on all rotor segments simultaneously. Also, the synchronized timing of the rotors assures that rotor interference never occurs assuring long life, consistent performance, and low parasitic losses.

The screw compressor is by far the best supercharger available today; it’s the only supercharger to provide a positive displacement design for maximum low-end torque as well as high efficiency for maximum top-end horsepower. No other supercharger in the world can offer the same unique benefits. Centrifugal superchargers and turbochargers either have significant lag time during shift points, on-off throttle response deficiencies, or inadequate off the line boost. Furthermore, Roots-type superchargers have been proven to be less efficient, especially at higher boost levels.


Whipple GENERATION II – Exclusive New Features

Whipple superchargers are the most efficient means of dramatic power increases on today’s modern engines. With Whipple’s unique 3/5 rotor profile, Whipple flows more air in smaller packages, at lower temperatures and drastically lower parasitic drag.

No other positive displacement supercharger compares to the potential airflow at such a lower compressor rpm. Whipple Generation II rotor profile has risen the performance bar again, with increased flow across the board, yet the identical rotor diameter and length, allowing even better packaging.

Actual Comparison Test

Key Points:

  • Whisper quiet operation, zero increase in idle noise (Eaton and other positive displacement blowers all have gear rattle at idle)
  • Generation II rotor profile increased volumetric efficiency to an average of 95-99% throughout the engines operating range (1.4-2.4psi), giving peak boost levels and maximum power throughout the rpm range
  • More air at lower blower speeds mean increased torque, dramatically increased throttle response for pure customer satisfaction
  • Increased volumetric efficiency allows lower blower speeds for decreased power consumption and lower discharge temps, which equals more power across the rpm range
  • Increased rotor sealing for less back leakage from high boost levels, which equals lower discharge temps
  • @ 1.6psi, with the Eaton TVS 2300 turning 14,000rpm, W140ax requires 15kw less power to equal the same flow.
  • @ 1.6psi,with the Eaton TVS 2300 turning 14,000rpm, W140ax produces 20deg C lower discharge temps for far greater power potential.
  • As compressor speed increases, Whipple 140ax continues to pull away from Eaton TVS. This allows for better peak horsepower.
  • Robust design for extreme applications, double angular front bearings that offer far greater strength than other positive displacement superchargers.
  • Whipple rotor profile designed to minimize rotor-to-rotor contact, ensuring that seizure is nearly impossible.
  • Advanced PTFE seals for 100,000+ mile reliability.
  • Cast aluminum housing allows for lower cool down time than billet housings
  • -Bolt on pulleys for simple boost adjustment (2 minutes)
  • Precision cut helical gears for quiet operation and trouble free operation
  • Whipple’s flow characteristic gives the best of all worlds, peak flow and low power consumption at low speeds for industry leading torque and throttle response, while increased flow and low power consumption at high rpms produces the best peak HP.

Superior Engineering

Every Whipple product goes through extensive research and development to ensure proper operation in all applications. Their standard development practice involves the measurement of over 100 parameters utilizing their own custom designed data acquisition computers. Measurements include individual cylinder air/fuel ratio from a true wide range Horiba sensor, individual cylinder pressure and cylinder combustion analysis as well as solid-state exhaust gas temperature.

Our expert automotive engineering team has over 20 years of OEM experience calibrating even the most stringent emission standards such as Partial Zero Emission Vehicles (PZEV), as well as powertrain system design and development. This technical expertise assures that each supercharger system is properly integrated as part of the overall powertrain. No other company has a more advanced staff in the field of powertrain systems and emission friendly products. Every product gets extensive R&D time starting with Superflow engine dyno based engine mapping followed by environmentally controlled wind-tunnel vehicle development that spans the range of ambient temperatures ranging from -20 to 130 F. Finally, each of our products is tested using a DynoJet Chassis dyno as a final validation. This ensures that you get maximum power from our product, as well as long trouble free operation.

Steeda Autosports and Whipple Superchargers – Delivering the BEST forced induction system and calibration system available today!