There are two different openings on the roots blowers a small and large. I don't know what size they change the opening, but if u have the large opening u will need a adapter to install a bird or bug. U can get them at goodvibration.com, rbs.com, and there are probably others, but that's who comes to mind quickly.
A forum community dedicated to performance boat owners and enthusiasts. Come join the discussion about offshore racing, performance, modifications, builds, classifieds, troubleshooting, maintenance, and more!