Carb sizing OK?

[Montana67]

Hello.
I have an Edelbrock 850 cfm Q-Jet carb I plan on putting on a fairly heavy built 383 for my '67 Camaro.
I'm concerned somewhat that this carb is going to be a too much for my 383. (The projected HP is 470-480).

Using the traditional carb-sizing formula dictates a carb no bigger than 700 to 750 cfm. However, I contacted the good folks at Edelbrock and they said that one of the benefits of the Q-Jet (and also the reason it has so many moving parts) is that the secondaries stay out of the picture unless the engine demands the extra airflow -- and that I shouldn't have any problems.

I'd appreciate any advice from you all on this -- particularly if you have a Q-Jet setup or otherwise have insights.

Thanks very much.