Holley/Demon Carb stumble

This main body is a 1.375 venturi for 1.75 base plate, will flow 825 cfm with your base plate. I have one of these in one of my carbs, works nice.

Search Results for 67107C

It will be here Wednesday.
It comes with main jets....Do you think i should start with them? Even though i Race at 6600 feet?