I carbonated a Hefeweizen to 4 volumes of CO2. I tried a bunch of different ways to dispense this. Everything from very long serving lines to a diy flow restrictor. I carefully went through the available guides on balancing a dispensing system and followed the suggested tubing lengths for each one. Everything I tried yielded glasses of foam.
I got this from More Beer...
http://morebeer.com/view_product/16270/ ... _Hand-Held
It works wonderfully. I was pouring perfect beers after a couple adjustments.

