About to install my MAP adjuster but...

[gradon]

Upping the pressure makes the injectors squirt more fuel when on. Upping the map voltage controls the pulse width/how long the injectors stay on.

[Cheromaniac]

I'm almost positive that I need more fuel but I won't know for certain until I splurge on a wide band O2. My motor defiantly pings under load (about 70% and up throttle) So I'm also between an adjustable MAP and and adjustable FPR or both.

Is upping the fuel pressure the same as adding bigger injectors?

Sort of but there's a limit to how far you can raise the fuel pressure before risking the injectors hanging open. I wouldn't go above 50psi so with the stock fuel pressure on Renix/OBD I models at 39psi, the maximum safe flow increase you'll get from the same injectors is 13% so you can make 21lb injectors flow up to 24lb/hr.
Pull your plugs and check them. If they're white you definitely need more fuel.