Conclusion 
The EEC-IV is a tremendously powerful engine computer.  When you also take into consideration that it was first implemented in 1984 and continued to be used in the Mustang until 1995 it becomes even more impressive.  The average home PC is now obsolete within two years, yet the EEC-IV was powerful enough to last for eleven years!  Granted once you begin asking the EEC-IV to manage a full race engine you will definitely begin to run into some performance limitations; however, for even highly modified street Mustangs the EEC-IV is more than capable of tackling the job.

Take this performance and add in the EEC-IV's easily accessible diagnostic features and the home mechanic is equipped with a powerful tool that he can carry anywhere.  With simple jumpers this tool can be activated whenever he, or she, thinks there may be a problem. Armed with this information it is possible to either fix the problem yourself, or ensure that your mechanic is not taking you for a ride.  If you happen to be at the race track the EEC-IV can help get you rolling again should trouble arise.  All in all we think you'll find the EEC-IV a nice piece of equipment to have in your Mustang toolbox.