Mark Houlahan
Tech Editor, Mustang Monthly
March 1, 2002
The Air Adjuster Dually is designed for the street enthusiast and the hard-core racer. Easy-to-use controls with a large, legible display are the first things you notice, while inside are military temperature-grade electronics and a fully potted, vibration resistant case. The Air Adjuster Dually is covered by Interactive's lifetime warranty (on the original purchaser's vehicle) and retails for $329.95 under PN AD-8222-F.

Horse Sense: Ford uses dual throttle bodies in many applications to minimize the initial throttle-blade, tip-in vacuum drop (versus a single large throttle body) to maintain air velocity. This improves low- and midrange power while keeping all of the added airflow available for high-end power. Installing dual mass air meters and ductwork simply extends that true, dual-intake path.

Having sufficient airflow for an engine is always high on an engine builder's list. Building a 400-plus-cubic-inch Windsor and then having it attempt to breathe through a stock throttle body, mass air, and ductwork isn't how top performance numbers are made. To achieve the volumetric efficiency and power for which the builder is calculating, the entire intake-inlet tract needs to be measured and constructed to aid in the proper amount of air delivery, not hinder it.

This is the reason that dual inlets feeding a common EFI application are gaining in popularity (such as the Ford Racing FR500). When you incorporate dual throttle bodies and dual mass airflow meters, the amount of air delivery can be increased substantially to support the requirements of the engine. In the past, having dual mass air meters meant having to divide the rating of the fuel injectors in half (per meter) and running custom electronics to handle every-thing. Now, with Interactive Systems & Technologies' Air Adjuster Dually, you can easily install and calibrate two mass air meters for dual-inlet systems.

Using the Air Adjuster Dually allows the two mass air meters to combine signals and then output one signal to the computer. Halving the signal is no longer required, so the meters can be calibrated for the proper injector size. The Air Adjuster Dually also incorporates an adjustable air/fuel ratio signal for rich or lean adjustments. The divide factor is also adjustable and fully programmable to allow you to set the signal strength according to the size, type, and brand of mass air meter. Finally, the Air Adjuster Dually's output to the engine control module is limited to 5 volts so that it will never exceed the Ford ECM parameters and cause a fault code, no matter what the voltage signals from the dual mass air meters are.