The carb jetting needs to be adjusted upward to deal with the increase of air under pressure flowing into the top. The high speed air bleeds will also need to be custom tuned for the application. If you have experience with building and tuning a carb its not that hard to do if not it would be best to get a carb built for the purpose and then learn how to tune everything from that point.
Ronnieroadster
What else needs to be done to the carb? Is there any seals or o-rings that need to be added or beefed up to handle the extra pressure the turbo makes? Can a Holley 94 or Stromberg 97 be modified to use with a turbo in a blow thru design?