Frequently Asked Questions

Do you make a supercharger kit for a 5.0 Mustang?

We make supercharger kits for Ford Modular V8 SOHC engines only. Applications are available for 4.6 & 5.4 liter engines in the following passenger cars and trucks:

96-02 Mustang GT,

94-97 Thunderbird,

94-02 Crown Victorias

94-97 Cougar

94-02 Grand Marquis.

F150 trucks


02 Explorers

We do not make a kit for the 4V motors in the Mustang Cobra or Lincoln Mark VIII

Please refer to the proper section of our website for additional info.

Will this fit under my stock hood?

All of our kits will fit under the stock hoods of the vehicle they are intended for. There may be some slight rubbing on the underhood insulation on some models.

Can I perform the install myself, or does it require a professional mechanic?

Our kits come with a very detailed, illustrated install manual,(which is available online). If you read the manual thoroughly and understand the procedures before attempting the install, you should have no problems. A certain amount of mechanical aptitude is required as is in any mechanical work, but if you would be comfortable swapping an intake manifold, this should pose no problems.

Will I need special tools for the install?

There are a few special tools you may need to buy before attempting the install.

Fuel line tools, mini tubing cutter, metric allen wrenches (or equivalent), torque wrench.

Will this improve my fuel mileage or hurt it?

While there is always the opportunity to utilize more power, your mileage may be less. However, if your driving habits remain equal so will your mileage. Your highway mileage will be virtually unaffected.

How much boost do I get and when?

We have different boost levels available on different vehicle applications. The Mustangs are 6-9 psi and the trucks are closer to 5-6 psi. This may seem like a low amount of boost compared to centrifugal products rating. The use of an Eaton (positive displacement blower) allows an almost constant boost level over the entire engine speed range. The centrifugal kits ramp up boost as engine speed rises, and are thus rated as a maximum. The average amount of available boost with a positive displacement blower is therefore higher even with a lower peak boost rating, and translates to a better driving and quicker vehicle. It also does not require the use of lower gears to keep the engine "in boost".

Ford uses an M112 Eaton and you use only an M90. Why donít you use the bigger blower?

We chose the M90S (90 cubic inches per revolution) many years ago, and for good reasons. The smaller blower needs to spins faster than the M112 to achieve the same boost level. This higher speed combined with a smaller sealing length means leakage at low engine speeds is reduced and low RPM boost increased. Our kits typically reach full boost by 2000 RPM. It would take up to 2800 RPM to reach full boost on the same engine, M112 equipped. The maximum speed of the M112 blower is also less than the M90 (due to longer and heavier rotors), thus negating the assumed higher air flow potential of the bigger blower. The M112 does posses better durability potential due to itís lower rotational speed, thus its existence.

Do you use a wastegate to control boost?

We use the blower pulley to control boost. A smaller blower pulley spins the blower faster and makes more boost. We do use a Bypass valve, but it is not to control boost. What it does is open an air flow path between the inlet and outlet of the blower. This allows the blower to spin freely in the vacuum of the intake manifold when boost is not desired. As soon as boost is desired (actually slightly before) the valve is closed. The benefits of this valve are reduced fuel consumption and quieter blower operation under normal un-boosted driving modes.

How much power can I expect?

Since all of our kits have a similar design, they provide similar power improvements. Typically a 40%-50% improvement in engine output is realized. Power curves are provided in the area of the website pertaining to your vehicle of interest. (most cases)

What other parts do you recommend I use in addition to the supercharger kit?

Additional bolt on parts such as exhaust systems, throttle bodies, and air filters will make viable gains. Changes in parts that will affect the proper fuel metering and emissions compliance are not recommended. Such as: Mass air meters, adjustable fuel pressure regulators, off road H piped etc. We also do not recommend underdrive pulleys and open element air filter systems that draw in hot air from the engine compartment.

Do you know of a install shop in my area?

Please call or e-mail us for the most current list of dealers/installers in your area.

I heard that he roots blowers are really inefficient and make lots of heat?

While roots supercharger designs of the past were less than stellar performers in regard to adiabatic efficiency, modern (modified roots) Eaton superchargers are quite good overall. Their overall efficiency at reasonable boost levels (4-8 psi) is quite competitive with other designs (screw and centrifugal). Combined with the quiet operation and 100,000 mile durability, the Eaton supercharger is the logical choice for OEMís and the aftermarket.

What is the difference between an M90 and an M90S?

The M90S that we use is a "ported" M90. The inner contours of the ports are rounded off and re-sculptured for better flow and efficiency. This is quite similar to porting your heads.

I recently came across a good deal and bought an Eaton M90 off of a supercoupe. I was wondering if it will be compatible with your kit?

Probably not! There were 1st, 2nd and 3rd generation M90ís on the Supercoupes. Only the later ones used the 3rd Gen blowers. Even if you have the correct M90, you would need a qualified machine shop to modify the nose drive housing and swap pulleys. There is also no guarantee that the blower is in good condition, so it is not recommended.

I hear that roots blowers are really noisy. Is that true?

The Eaton supercharger is very quiet, probably the quietest blower on the market. Old, two lobe, straight bladed GMC style roots blowers are quite noisy, as are the centrifugals. If youíre worried about noise, don't be. The Eaton blower was developed specifically for OEM applications, like the Buick, Thunderbird Supercoupe, Jaguar XJR, etc. and uses a teflon coated, three blade, twisted helix design. At low power levels the blower is close to imperceptible, but during hard acceleration it will emit a satisfying audible whine.

Updated November 9, 2003

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