Quote:

lets clear things up.

there are 3 types of nitrous systems.
Dry, Wet and direct port.
The Dry system is purely a jet (or 2 or whatever) that is put in the intake (usually 12" from the throttle body from memory) that supplies only N2O.

The Wet systems are a fogger nozzle that is also placed in the intake. however these systems supply a seperte fuel (usually of very high octane content) aswell as the N2O.
the benefits of the wet system is that it reduces detonation more than the dry system.

There is also a Direct Port system that is a seperate fogger nozzle for each cylinder. these nozzles are put in the intake trumpet (close to the injector.
these are even better systems because of the greater amount of N2O supplied by the extra nozzles aswell the N2O is "fresher" (closer to liquid) which creates a denser charge which helps combustion etc.....
these direct port systems are good for up to a 200hp kick!!

Now, back to the issue.
A 50hp shot would be a dry system, which means that no extra fuel would be added.
however more fuel may be needed because of the more oxygen present.
so as mentioned in a previous post an electric fuel pump and bigger lines may be needed.
the jets shouldn't need to be touched, as long as they are big enough to keep enough fuel for the added oxygen in the chamber.

In my opinion i wouldn't put nitrous oxide on a stock A15 or any stock engine until it had a few other mods.