You can get a turbo from a junkyard thunderbird turbo coupe (many of these were manufactured). and since it has the same chassis/engine management system, you swap over the turbo/injectors and all the turbo hardware stuff and also the computer from the turbo coupe (i've never done it, but i think this is most of the stuff, there's probably a few other things as well). you can also get an intercooler from an SVO mustang or i've heard a turbo VOLVO intercooler will fit somewhere in the engine compartment. This should give you MUCH better performance than your 105 horsepower (i'm assuming your car is a '92 or '93 from what it looks like), more around 175 without the intercooler and easily 200 with it (like the SVO). The camshaft may be different on the SVO as well, but i'm not so sure on that one. Good luck, hope this helped.
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'84 Mustang 5.0 LX
My car