How much will my cam effect my carburetor build?

My engine is off at the builder but in the mean time I was going to rebuild the Holley that would be sitting on top of it. The Holley is a used unit off Craigslist so I know NOTHING about it right now. Should I wait to hear what the build recommends on the cam before I start building the Holley?

Engine is a .30 over small block with flat tops and aluminum heads. Carbuerator is a Holley 750 DP.
which small block? big difference in requirements between say a 273 vs a full out 408, 360 based stroker.