I currently have a 93 dx with aem intake spraying 45 shot dry...about to get fuel pressure regulator and rail...my friend has a safc collecting dust in his garage he was going to give me...will it help me tune my car or is it just a waste of time.

 

You say you have a dry shot? how are you adding fuel currently? don't bother with the fuel rail, it's not gonna help anything, same goes for the regulator unless it's part of your fuel management. The AFC is not gonna help unless your Nitrous is always armed and comes on with a WOT switch. The AFC will richen/lean the mixture all the time not just when nitrous is flowing, the AFC also advances the timing automatically when you use it to add fuel(not a good thing). hope that helps.