Why are you upgrading your fuel system? Did you get bigger turbo?

What's the flow rate on your stock pump?
I know that w/ my car, some people get a higher-rate pump or a Skyline fuel pump (eventhough it's close to a stock 300ZX pump). However, the stock fuel pump supposedly can support up to 750HP. I'm not sure if that's accurate, but I know it is good for at least 500HP. So upgrading that part is a waste of money.

As for injectors, the size will depend on what you are doing w/ the rest of the car. Again, need to know what major changes you have made.