Well the reason to swap out a 93 Cobra computer is it takes 7 seconds to go in to open loop and it pulls a ton of timing out on the top end and really hurts performance at the track. Some people find the AL9 works great, anf you coukld thenm add one of the aftermarket tuners like a PMS or EEC-TUNER to fine tune all the aspects. If your planning on major mods in the future you may want to look at a Aftermarket computer such as a SpeedBrain. We had good sucess with the Speedbrain on my dads 93 Cobra but it is a learning experience and takes some knowledge about the EEC system or you could create major problems.
84 is right make sure you get a computer that came out of a car of the same transmission, A/C, etc..
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