Planning the Conversion There are several ways to go about making the conversion on 1987 to 1993 pickups or Broncos. However the preferred method largely depends on the type of transmission you have. If your truck has the E4OD automatic transmission (typical on the 351 and 460 equipped trucks and 93-95 Lightnings) then you have to consider that this transmission is controlled via the engine’s computer. The most common mass air conversion calls for using the 88-93 Mustang computer, which does not have E4OD control. The options in this situation are to use a 1995 or 1996 F-150 or Bronco computer, as by that year the trucks were mass-air and all running E4OD’s. Other E4OD owners have creatively performed the mass-air conversion using the Mustang computer to control all the engine functions, while retaining the stock speed density computer to handle the electronic transmission. Finally, many have taken the more drastic approach and replaced the E40D with an AOD, C6 or manual gear box. Either way, if you have an E4OD equipped F-150, Bronco or Lightning and want mass air, you have some research to do. Spend some time at the National Lightning Owners Club (http://www.nloc.n...