I have an 08 Malibu LSV with the Hammerhead engine. For the first year I had the boat I remember being able to hit about 43 MPH before the speed topped out, and no more speed was possible. No rev. limiter would ever kick in. I don't remember ever looking at how many revolutions the prop was spinning at though. This year, I can't seem to break about 37 MPH. The difference is what I guess can only be the rev. limiter kicks in right about 4800 RPM (or 48000, whichever makes sense). I don't have my owners manual with me and I can't figure out what the rev. limiter is set at or even if my boat has one? The reason I think its the rev. limiter is simply because right at the same point, the engine quickly and breifly drops power, and the RPS drop slightly. It takes about 2 to 3 seconds to bring it back up, but feels exactly like a speed governor in a car.
Does anyone have an explanation for this?