Hat spacer

Robert the spacer is to increase airflow into the blower by moving the injector hat forward and lessening the angle that the air has to turn going from the hat into the blower and to match the opening of the bottom of the hat to the opening of the top of the blower. A lot of times you have to adjust the top opening of the blower based on what overdrive is being used. Most times a small overdrive requires a smaller opening in the top of the blower which is increased as the OD is increased. So if you have a 11.0" opening on the bottom of the hat a 9.5" opening on the top of the blower the incoming air is going to see a big step and is going to disrupt the airflow going into the blower and power is lost. If you hat opening matches the blower opening so the air flow is smooth with no ridges then the gain of using the spacer is not as much as if there is a big mismatch. If you have a big mismatch then the right spacer can really help. The mismatch can also be the other way around if the hat has a 9.5" opening and you have a 11.0" opening on the blower. If you stick the hat right on top of the blower then there is not much point in having a 11.0" blower opening but if the spacer is matched and the hat is raised up then you can have a lot of gain. The best way to get a spacer is to contact some company like DMPE and trace the blower opening and hat opening on pieces of paper and get the spacer custom made to match both. Don't just go out and buy any spacer unless it matches or you may add turbulence and lose more power.