Running a dry Nitrous system can potentially harm your engine, reason being is for the first few seconds while the Nitrous is injected your engine will run extremely lean due to the extra oxygen in the nitrous.
The bigger fuel pump and injectors are needed to compensate for the lean condition once the O2 sensors see the extra oxygen in the exhaust, and the PCM can add the fuel.
With the 05115 dry nitrous kit, the kit does not start flowing nitrous to the inlet tract until there is sufficient fuel pressure to provide enough fuel. If anything the mixture is a bit rich for an extremely brief moment.
May or may not need pump and injectors, I've heard of people running it on completely stock setups, but I have did not run it while completely stock.