Well, here are the recalls on a 98 Cobra:
http://www.internetautoguide.com/aut...mustang/cobra/
The aftermarket parts are there for the power you are wanting to make, but they are expensive...
Most likely you would be looking at some type of centrifugal supercharger setup that will probably get you around 400 RWHP.
Modular parts are numerous these days, but expensive compared to 5.0 Windsor parts.
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