RBS wants to talk about the importance of the leaking down of your barrel valve when running fuel injection.
An improperly set barrel valve can result in off idle stumbles or overly rich conditions. To leak your barrel valve down you must block off all injection lines on the barrel valve but leave the hat nozzles open. Connect your leak down gauge to the air line of a compressor if you are using a dual leak down gauge tester. Set the pressure to 100 psi on the first gauge then connect the tester to the inlet fitting on the barrel valve and read the leak down percentage on the second gauge. If you have a single tester do all the same steps and read the leak down percentage on the gauge and adjust the barrel valve spool until you achieve the percentage of leakage you desire. To change the percentage off the leak down. It is very simple task by simply cracking the two nuts loose on the barrel valve and rotating clockwise or counter clockwise, here is a little saying to remember "LEFT IS LEAN, RIGHT IS RICH." A leak down gauge is a good tool to have it allows you to test leak down on your engine barrel valve, or poppets in your fuel injection system.
Leak down testers are available under (TOOLS) on RBS webpage