[rohrmann]

I don't think it's wise to go much over 55 or 60 psi, too much risk of serious leaks in your plumbing system. What you may want to look for is more volume instead of more pressure, but with the 1/2 inch plumbing in these rigs, even that will not improve much. Also, if you do any boondocking, you will just run out of water that much sooner.