maccavr4, can you please start to use punctuation in your posts, it makes it easier for us old farts to try and help you out.
As GVR40 said, most will only work well when flowing in a particular direction, if there is an arrow on the side of it, this usually points towards the turbo but consult the instructions for your particular boost controller. They should also tell you which way to turn it to adjust your boost.
If in doubt, take it off, blow in the opposite end to that connected to the turbo (e.i. the end which connects from the intake piping) and turn the knob. If you cannot blow through it, this means the wastegate actuator sees no boost and therefore does not open up the wastegate which means you will run 20+ psi which is way too much if you are still running standard injectors. Wind the knob the other way until you can blow through it easily and install it on the car in this configuration. This way, you should only be running stock boost (8 psi). Slowly wind the knob in until you reach your desired boost level.
"What sized injectors could i run without it losing power? How big should could i go?"
That will depend on how much boost you are going to run.
What boost level does your turbo run out of efficiency?
Are you using the standard fuel pump or a Walbro/ Bosch etc?