260DA WOT under load?

[JeffM]

I thought I saw this discussed before but couldn't find it...

Last weekend I ran our 5.7 EFI up to WOT and only got 4,250 rpm and 35.5 mph. According to the manual, it should be between 4,400 and 4,800 rpm. However, we were loaded for a long weekend, two adults and two teenagers, full water and fuel, clothes, kitchen sink, etc.

Is a drop of 150 to 550 rpm due to the load reasonable or should I be concerned that we didn't get into the proper range? My gut reaction is that we're okay but I want to get the experts' opinions.

Thanks!
Jeff

 

[Dave S]

Do you have any bottom growth at all. If so that can slow you down as well.

Since our hulls, engines, and boat weight are a bit different I can't make a direct comparison. However, on my 260DA, the heaviest load I ever had was nine people and it only slowed me down by about 2 mph on top end as I recall.

 

[JeffM]

Thanks, Dave...

The bottom and outdrive are clean -- we had her out of the water for some gelcoat work last Saturday and I checked the bottom then.

We also had the props trued and polished (but not scanned) this spring.

The outdrive was trimmed up slightly to maximum rpms, and I had the tabs completely retracted.

Jeff