Nitrous kits

I want to add a wet nitrous kit to my 91 toyota mr2 turbo. Im not sure to go with direct port or not?? Also im running the max boost on the stock turbo 15 ...so therefore i know the injectors are pushing there limits. So i was wondering if adding a 75 shot if i would have to upgrade the fuel injectors, pump etc?? and info. would help guys thanks!

15 psi on the OEM turbo is not pushing the limits of the injectors ... it is pushing the limits of the efficeincy of the turbo.

I have pushed much more HP from a much bigger turbo on the factory injectors. There is a lot of fuel there :)

Sorry, I have no knowledge or expereince with nitrous to answer the meat of your question.

Im currently running a 75 shot NX wet system. So far, I have not encounter any problem. We also installed the same unit in a MR2 Turbo ver.4 and also did not encounter any problem. Just remember to change to a colder plugs. Very important.