Dislexia strikes: maximum surge discharge volume = MSDV, or VSD(MAX)
I also meant to mention, if you have one of those 1.5 gallon toities, you can always wait a minute for pump to catch up before you do the second flush ... and then a minute before you do the third flush ... however many times it takes to get the #2 down the hole. The "repetition rate" doesn't have to be added into the calculation for the surge volume, unless you just want to.