You can start with no boost jet, as kkrofft said. If you are not getting enough boost, then install a jet with a large hole, like .060 for example (be careful of overboost at all times). Then simply install smaller jets until you have the boost you want. .... Some have talked about the difficulty of getting different sized boost jets. I just made my own with 1/4" dia aluminum. I chose the drill bits I wanted to try at the local hardware store.