OK, I'm trying this again. I figured out what I did wrong last year (it had to do with the little screw on the side of the air inlet) and plugged my little Porter-Cable compressor in last night.

It seemed to work OK on the closer sprinklers but on the ones farther away, it didn't seem to have enough 'power' to blow them out.

So here's my question: What specific "number" do I need to be looking at to give me enough power to blow the sprinkler lines?

My current compressor is as follows:

Porter Cable C2002 Compressor

PSI: 150 max
Tank: 6 gallons
2.6 SCFM @ 90 PSI

So what "number" do I need to be bigger? Would a bigger tank help? A bigger SCFM rate?

I don't mind shopping around for a new compressor, but whatever I get, I want it to be big enough to blow my sprinkler lines once and for all (without damaging them, obviously.) I had my compressor running for ~ 2 hours yesterday (I'm sure my next door neighbor hated me!) just trying to get it to get up to 150 PSI before I turned the pressure on to the sprinklers, but it would give me one "blast" of pressure and then not much more after that.