I have stock 19lbs injectors, a 12 to 1 plate in my FMU, and have plenty of fuel pressure, the way I understand it, my stock regulator doesn't work underboost any way because it opens all the way. What advantage would a regulator do for me and what brand would I buy if I need one
A regulator would allow you to make your injectors act bigger (all of the time, unlike your FMU, which makes them act bigger when under boost). It's not necessary, but fun to have. I'd get bigger injectors instead and lose the FMU altogether. If you want to get a regulator, Kirban is the way to go.
For one it makes tuning the car a breeze. FMU's are just a big bandaid for running small injectors. Ditch the FMU, install the correct size injector for you mods and I bet the car runs way better. Most of the time FMU's cause a rich problem at idle. When we ditched RC's FMU his car sounded way better at idle and according to him ran much better. Dave is right on about the Kirban.