When using nitrious, It is IMPORTANT to remember that ANY dip in fuel pressure will kill you! If you run a wet system, which I would with the TBI, you have to make sure there is enough fuel flow. Stock TBI pumps are NOT made to push as much fuel as you may need. One of the keys to keeping a stock or mild engine to last, is SAFETY devices. Low fuel prussure cut off, ignition retards, If you are running some kind of rev limiter, the nitrious MUST be shut off before the ignition is pulsed, or it's KABOOOM!!
When we were racing street with Nitrious, We used Jacobs "nitrious Mastermind" controllers. They have your safety cutoffs built in, your ignition retards, they shut off your Nitrious 50 RPM before your ignition gets pulsed for rev control, Thet are also a progressive set up for the juice. You can set it to start at a certian RPM at 25% and slowly pick up to 100% as RPM's build. MUCH safer than many W.O.T. set ups. This GREATLY reduces the Initial engine shock when the juice is applied. The use of this controller, will allow you to use a larger kit, safely, on an old tired engine! If engine RPM's are not high enough when the button is pressed, rods bend.
Depending on the size of the kit you plan on using, I would consider a seperate fuel line just for the Nitrious system. If you are just gonna stick with a stock system, I would stay with a 100 hp type set up.
ALTHOUGH, Nothing will achieve the visual impact of A BIG 'OLE BLOWER!!! Nitrious, if used CORRECTLY can give you some awesome, RELIABLE power gains.