Never seen a wasp major with the superchargers in place. They are quite daunting on their own!
But more on topic, If you have a two stage design, with both stages at say 3:1. If the final stage puts out say 100 cfm it would need to ingest ~300cfm. So wouldn't the first stage need to put out 300 cfm, or ingest 900 cfm, requiring it to be a larger unit?