Just wondered, does this come in a speed density and a mass air version, or are those parameters in the chip only - with that being the variable ?

 

The A9L and A9P are Mass Air.

 

Ok, thanks

 

The more accurate way to put it:

The Ford EEC-IV computer came in mass air and speed density versions. The A9L (among many others) is a mass-air version.

 

Ok to both of the responses, but here's the next question - when it comes to tuning them and or getting chips, will either work just as easily with the required and have similar costs, and also for software and other outside aftermarket attachments ?

 

The easiest way to describe it, is that while every Ford vehicle from ~1985-1995 used the EEC-IV computer, and they all have very similar hardware inside them, the actual software/code inside them is very different - even for the same model year of vehicle. It's not like a PC, where the computer is running Windows and you can run whatever program you want on it. The code for each EEC-IV computer for each engine type is unique with different parameters hidden in different places.

The tuning program uses a file called a "strategy" file. The strategy file is a "map" that tells the tuning software and your tuning chip where those parameters are hiding.

The "A9L" thing is called a catch-code. It represents the particular calibration (or tune) that computer has. The Mustang A9L and A9P use the "GUFB" strategy, which is a very well documented strategy and widely supported. Everyone knows where everything is inside of it, so you can tune everything.

Other well supported strategies from this era are the CBAZA '94-'95 Mustang computers, and the AHACB (Catch codes HOG0, HOG1, WAY1, VEX1) mass-air truck computers from 94-95. Very few of the speed-density EEC-IV computers are supported well - generally only the first-generation Lightning computers and the ~'86 Mustang 5.0 speed-density computer.

Now, that's not to say those are the only speed-density computers you can tune - there are some other speed-density truck computers that have strategies available for them. The problem is they are often well fleshed out - meaning the "map" is "missing pieces". So you'll be able to tune some aspects of the truck, but not everything. They generally also have issues with many datalogging parameters being missing.

In general, if you want to mass-air convert and tune these trucks: Convert to A9L if you have an AOD or 5-speed, Convert to WAY1, HOG0, HOG1, VEX1 if you have an E4OD.

 

Another note... there are actual hardware differences between these two types of PCMs. These V8 MAF systems use sequential injection and a MAF meter and while the Mustang PCMs also have a MAP sensor the truck PCMs don't, so for example there are hardware drivers in these PCMs for each injector and the MAF meter while the SD box only has 2 injector drivers(one for each batch) and no MAF ports at all, so you can't "reprogram" an SD PCM to make it MAF because the necessary hardware doesn't exist on the board.

 

Thanks Ian and Paul, slowly I am getting there .....