Will a chip give you gobs of power? No it won't. It will give you some. I did notice a difference with mine, although compared to just running with advanced timing, i would have to say the difference may not be something you can feel.
The big difference with a chip in the EEC-IV computers is that (atleast with mine) it makes the car run better. My car hunts a little some times with out the chip. With the chip it runs good.
The guys in the Fox bodied stangs forget how screwy our 94-95 computers are some times
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I would get a custom chip and a dyno tune, but you are at the same point I'm at, and I don't think for the amount of modifications we've got it is really worth it, yet
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