fuel injectors

is there a way to get larger injectors with out spending $280

Yeah, go to the junkyard. But I doubt that will help with your oil burning problem. If I'm not mistaken the Si injectors are 240cc and that I would think is all you need for N/A application. If you don't think you're burning enough fuel, perhaps you should check your fuel system components.

Are ZC and Si injectors the same size?

almost all honda injectors are the same size save for the newer H22A.