yep you need to 'balance' your system, so that serving psi is the storage psi, which gets you the CO2 volumes you want for the style being served.
I run about 12psi, with 8 feet of tap line to balance it out. More line = resistance so the beer doesn't rocket outta the tap and foam.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10