i hope you're not expecting much from a 2.3L with an auto
, One thing i know you can do is to take off the intake muffler between the throttle body and the airbox (big black plastic thing with the ford logo on it), and taking an exacto knife or something and cutting out the inside (cuts off like 1/2" of the already tiny 2" intake diameter). You can also most of the bottom of the air filter housing off so it flows more air. If you have stuff to port and polish that'll free up the most amount of power for the least amount of money. I've HEARD, this may not be accurate, but i've heard that you may be able to put on a throttle body from a 3.8L V6 Thunderbird and match the intake manifold to the throttle body. There are companies that make cam sprokets that allow you to adjust cam timing and that could give you i think up to 10 horsepower even on such an anemic engine. You might also be able to make the stock right side 5.0L exhaust fit up to the 2.3L (you'd have to do some welding to make the pipes fit together from the 2.3L to the 5.0L exhaust) and seal the H-pipe cross over to have lower restriction exhaust. I hope this helped.
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previous name: 84stangLX
'84 Mustang 5.0 LX
my LX
'89 Mustang GT
my GT