New York Mustangs
AdirondackFox08
For a fox, I would do a hci and put a Vortech on it. That is probably the simplest and "cheapest" way to make as much power you can before splitting the block in half.
Noterminator
Plus 1 get a Vortech for the Fox. Also since no one mentioned it, there are superchargers, and turbos. Procharger is a supercharger brand.
ROUSH 4
Vortech on the fox...............
FrostByte
There are multi page threads that discuss this. None are better than others until you know exactly what you want.
FrostByte
Turbos & SC are the same except for the way the get spun. SCer use a belt & turbos use exhaust gases. Turbos have heat issues but they dont have as much parasitic lose as a SC. It takes more HP to spin a SC than what u lose to run a turbo so u get more HP to ground w/ turbo. ProChargers are jsut a superior brand SC.
RusWolf
PC is a type of a supercharger. It all depends on your goal and needs. From my experience superchargers require less maintenance. If you go with PC make sure,to get helical,gears or it will sound absolutely disgusting on idle. Also look at vortech/paxton they are the same type as PC called centrifugal supercharger. They look and operate just like a turbo BUT are belt driven.
AdirondackFox08
If you want to get the most hp you can get, you had better invest in a dart short block or you will find yourself with a split block. The stock blocks can last for a little while around 450 to 500 rwhp, but it's borrowed time for the most part. A lot depends on the tune, but block just isn't strong enough for that much power.
Noterminator
Like Josh said get a stronger block. The old 70's Mexican blocks, the R block, like he mentioned the dart blocks, etc, will all work great. Most sites also state the power capabilities of each block. After you get that all situated then I'd look into something like the YSi, F2, F1-A, etc. Those are some of the race/ strip ready superchargers capable of big big power numbers.