Same intake. Same carb. Probably the same jetting. Your friend is a total moron.
Q-jets are vacuum operated anyway. They respond to engine load. GM used them on 4.3L V6s and all the way up to 454s.
Even if it was bigger it might not mean that it'd be metered wrong. I've got a 500 CFM Edelbrock on my 350 and it's jetted WAY too rich. My truck even smokes black at times. I can't believe I'm actually going to have to jet such a small carb LEANER.