PY and SP Cruiser speeds

I have seen claimed speeds all over the place for these boats in different articles. I just had a PY Cruiser surveyed with the 4jh4-hte Yanmar engine and at WOT it would only do 7.8 knots, which was quite a bit less than I thought it would do after reading this data from a review of the PY:





This boat had the 4jh3-hte engine but it's pretty close to the 4jh4 it seems, other than the higher RPM, but the speed numbers of this test are waaaaay higher than we were able to get. At 2500 rpm we only got about 6 knots, and they allegedly got 9.6? That's a huge difference and I don't understand it.

The bottom had a little growth but not much. We had 3/4 full tanks and the boat in the text had very little fuel, so we had probably 1200lbs more weight there. What am I missing?

What speeds do others with PY or SP (same hull and engine I think) get?

Thanks!

Article is here:
www.powerandmotoryacht.com/boat-tests/is...acket-py-41?tab=test

While I can't offer first hand experience on the PY and SP, I can offer a real example of a similar situation. The owners in our club each purchased the same boats but different years. A 2006, 2007 and 2008 Hunter 33. They are very similar in equipment, the same diesels yet each motors and sails differently. The 2006 is by far the fastest of the three, the 2008 the slowest. Hauling them, we discovered that the previous owner of the 2008 had swapped out the factory prop for some reason(damaged?). The prop was suspect as far as proper pitch and was a three blade vs a 2 blade. The prop on the 2006 also turned out to be switched, the PO put on a folding prop which was partially responsible for the faster sailing speed but was also pitched to increase motoring speed.

Is it possible that your potential new boat was re-propped at some point?