Here's what I know from my experience:
RC injectors have a different type of connector, so you gotta cut the factory connectors & splice in RC ones. Stock injectors are 240's, 270's ought to be such a small difference, not even noticeable. I had stock, then 440, then 310, now I have 370's (with a single turbo). If comptech doesn't say anything about changing injectors, I wouldn't go to 270's, I beleive it would be a negligible difference with the added headache of changing the wiring.