Split Second ARC2 80-mm MAS
by Jeff Lucius
This is the Split Second ARC2 MAS I used to have installed on my 1992 Dodge Stealth R/T Twin Turbo. It is advertised as a 83-mm MAS. However, I measure a nominal 80 mm (~3-1/8") at the narrowest inside diameter, which is at the rear of the hot-wire post. This "F8LF" MAS is designed for 1998 4.6-L engines using 19 or 24 lb/hr injectors such as found in the Ford Mustang GT and Cobra, Expedition, and F-series trucks. This MAS is 4" long without the 1" long air filter adapter. Air filters with a 4" ID at the mounting end fit this adapter. This MAS fits perfectly in the stock intake hose once the hose is coaxed into a round shape from the factory oval shape.
This hot-wire type MAS replaces the stock Karman-vortex type MAS and uses an electronic device to convert the analog voltage signal (representing mass air flow) to the square-wave voltage signal (frequency counts that represent volume air flow) that the Mitsubishi factory engine control unit wants to see. The ARC2 control unit sends fixed or constant signals to the ECU in place of the stock MAS's air temperature and barometric pressure variable signals. This permits easier calibration and translation of the ARC2 MAS signal and allows consistant manipulation of that signal by the factory ECU.
More info on the ARC2 setup:
Page last updated April 20, 2003.