So if everything else stays the same, that is, fuel pressure and pulse width, would a simple upgrade to bigger injectors cause my O2 values to be screwy? I had a set of old 30lb Accel injectors and I figure I'd put them on the car since it sat for a while and my blm's are sitting at 160 instead of 128.

Is the tune set up to run the 30lb injectors?

Nope. Its set for stock injectors. I will get it tuned but I wanted to know if this us te reason or if something else is wrong.

well if your truly going from 24 to a 30 # injector and no tune was changed then you should be rich like you thought. check fuel pressure and maf

Fuel pressure is stock for now and I just replace the maf due to another issue. I'll get it tuned as soon as it's roadable.

so you checked these ? or you guessing nothing is wrong

Yes I checked them.

Likely one or more of the injectors is stuck closed from sitting on the shelf. Send them off for cleaning and flow testing.