WOT 6V92’s realistic cruising speed ‘81 43c

[Hat43c1981]

WOT 6V92’s realistic cruising speed ‘81 43c

Our 1981 43’ convertible w/hardtop is powered with twin turboed 6V92’s and I am wondering what the WOT RPM should be under load. Also I run about 15kts with 7/8 full of fuel at 1880-1900 RPM’s depending on sea conditions. Are those figures I should expect? She is a heavy old girl and we love her. Not concerned about going faster, just wondering what I should expect as far as cruising speed for our Hatt at that RPM. Thanks!

 

[SKYCHENEY]

Re: WOT 6V92’s realistic cruising speed ‘81 43c

They should run up to 2350 WOT loaded and 2500 no-load. I typically ran my 6v92's at 2150 to get 16kts in my 53.

 

[madhatter1]

Re: WOT 6V92’s realistic cruising speed ‘81 43c

What Sky said on the basics. A 43 should do a decent cruise at 1800-1900 or so. If over propped as some do you kill performance. Slightly under propped will yield better performance overall. Plus engine temps will be better with more air passing through and a bit lighter load.

Proved that out with my own boat.

 

[Bob Bradley]

Re: WOT 6V92’s realistic cruising speed ‘81 43c

I ran a 79 43c with the same engines. Cruise around 17 to 18kts depending on how heavily it was loaded. Dry and freshly painted in the spring it could top out at 21 or so. Heading offshore with 2500lb of ice, full water tanks, full fuel, and a 300 gallon bladder full of fuel up on the forward deck, I could barely get on plane, and cruised at ab 15kts

 

[Hat43c1981]

Re: WOT 6V92’s realistic cruising speed ‘81 43c

Thanks for everyone’s responses. 15kts is a great cruising speed for us and allows us to sit back and enjoy the ride! Cheers! Any thoughts on what our props would have been from the factory?