You're welcome. I've noticed with SRs I've owned that were gas powered, that speed was heavily dependent on weight. My most comparable boat to a 330 was a 370. While it did not handle rough water well, it could be a real speed demon in a one foot chop. With full fuel, 3350 rpms, it would run about 20-21 knots. An hour later The rpms would start to climb as did speed. At the end of 6 or more hours, if the water was still relatively flat, the boat would indicate 28 knots on the gps at 3350 rpms. It wanted to go faster and at 3500 It would do 30 knots, but I always pulled the revs back to save the engines. I suspect the 330 is somewhat the same. Water and black water tank levels effect speed as well. The 370 was light for its size and I kept a full fresh water tank when running on Lake Michigan because the extra weight helped the ride comfort. So these are other variables that will effect what your speed as well as mechanical condition.
