We bought the 411 with Cummins QSB 330hp engines and immediately requested an upgrade to the optional 380 hp versions. It has taken a while to get this arranged but since I have been dealing directly with Cummins things have been moving forward nicely. The upgrade involves reprogramming the chip which controls the engines and, according to Cummins, should not take very long.
In order to give us some clear comparative numbers for the upgrade we decided to haul the boat, clean her bottom (and grease the running gear) and then do some sea trails. We also took her for some speed/consumption tests before the haul to judge the effect of a dirty bottom on the boat's performance. The results were interesting.
I am very glad we decided to haul the boat. It was amazing how much barnacle growth we had in the past two months. Here are some graphs of test results before and after the haul-out.
It is interesting to note that fuel burn is down and speed up at all cruising speeds. Also, with the bottom dirty, we could not reach WOT - bad for the engines. Next I will post the same comparative numbers after the upgrade.