I like a 60/40 area split (hat/port) until you reach about 7 GPM through the blower (at 8000 RPM). Then I start skewing the ratio to make the ports a larger percentage. My feeling is that blowers don't compress liquid...just air. By putting too much liquid through the rotors, you're hurting output. Naturally, the bigger the blower, the more you can get away with. That's just my rule of thumb and it has worked well for me.
The size of pump required really is determined by how fast you plan to spin that blower in this case. If you spin it straight up, you could get by with a 10 gallon pump just fine. If you're really spinning the snot out of it, a 15 or 17 gallon pump might be required to have enough bypass area left to tune with. Ultimately, it's about how much HP you're going to be making and having the fuel available to support it.
Lots of factors determine the minimum required inlet line size...distance from tank, height above fuel level, returns on the inlet side, etc. For most deals, a -12 is ok up to 12 GPM, but a -16 would be better. Above 12 GPM, I wouldn't use less than a -16 or 1 1/4" hose.
Spud
