One of the questions I am often asked in regards to moving a 2 1/2" interior is how labor intensive it is. The answer here is training, if you train with it you can do it. Some tips we found that work for us is:
Start low .....Like Russ said start off at 40 psi NP. It think most people against using a 2 1/2" have had a bad experience with a line over pressured. Hose line... we have found that using the rubber coated nitrile (wash and wear) hose is lighter and moves around corners and obsticles better than the fabric coated hose. Russ I am a fan of the Akron 1400 myself.. good tool.
I'd just note that the above number come from physical science, and therefore never change, if your testing shows something different, check your measuring gauges.Depending on which manufacturer you believe, at 50 psi a 7/8" SB should flow around 161 gpm and 15/16" will give you about 182 gpm. Of course, it's always best to do your own testing...