[The Deuce]

For what its worth, not all Nitrous Oxide is NOS. They're a CA based company who produce Nitrous Oxide Systems. Zex makes a great 'cheater' kit. Small shot, easy installation.

Hammer's right on here. Grab some PI heads, either from a 99+ GT or any 5.4. The Bullitt intake is pricey, but cheap speed never lasts.

In terms of motor problems, I've seen juiced cars throw rods and blown cars split blocks. It happens when you race. If you do it right, the parts will last. A throttle body spacer and a 75 shot would be a good temporary solution if you're looking for one. UPR sells a spacer that will accept a nitrous nozzle for $90. I was thinking about picking one up, even though I won't spray mine. Personal preference.

Have fun.