Thanks for all the comments. The engine and carb are new, not rebuilt. the carb is an edelbrock 1409 marine carb. From what I've seen, the problem isn't an overactive secondary but more of non-responsive carb. The RPM drops off about 50 RPM and PP is telling the engine to pick up RPM. I've run the boat with the engine cover off, and PP is aggressively pulling the throttle forward. Eventually the engine responds, but PP has been saying to pickup RPM and nothing has happened. Then, the engine finally responds and surges around 100 RPM. So you're getting a net of +/- 50 RPM which is way too much. My friend I ski with has a MPI 350 Mercruiser and the RPM variation is only about 10 RPM.  I've heard that the Holley has a primary and secondary accelerator pump but the Edelbrock only has a primary. I've been able to reproduce the problem at 30, 32 and 34 MPH, so the problem doesn't appear to be isolated to a certain speed. Tomorrow I should be getting my metering kit and will give it a try. The vendor I bought the engine from could have provided me with either a Edelbrock or Holley. Seems they didn't provide me with the right configuration for a tournament ski boat. Â