I run the Nitrous Express kit on my 01 cobra (EFI Kit for FORD). I have it jetted for 100HP and went 1 stage colder on my spark plugs.
Just be sure you do not run your platinum tips with anything over 50HP as you will either burn the plugs up or even worse damage your engine.
I bought mine used (had three shots on it), but I know you can get them new for around $579