400 CFM per ton of cooling capacity on the highest fan speed is standard air flow for almost all brands. So a 3 ton blower will deliver 1200CFM. A single stage furnace will have a basic 3 or 4 speed blower, so the datasheet that comes with hte furnace will tell you which speed is best for the cooling capacity installed.
You do know that a furnace output (BTU) should not be sized for blower capacity. Although some furnaces sizes are available in different cabinet widths/blower sizes. For example some 80k BTU furnaces can come in a 3 Ton or 4 Ton blower.
Trane furnaces model numbers generally have a number at the end that indicates the blower capacity (2,3,4 or 5).
You might try asking this question in the professional forums.