Carb to EFI hp gain?

[DOOM]

Had a conversation with a friend over the holiday week. We talked about hp gains from Carb to EFI . I used my 620 horse 572 pump gas crate engine as an example. I say hp gains would be very small maybe 5 to 10 hp. He thinks more like 20 to 30 depending on what type of injection . I don't think so what do you guys think????