43fbdc speed, pausible or not

[micky]

43fbdc speed, possible or not

I met another 43dc owner and his boat is a fly bridge model, he has the same engines and transmissions that I have and his props are 24 x 25, he told me that he cruises at 1800 rpms at 14 knots, my boat without the fly bridge and my props are 24 x 24 at 1500 rpms I'm doing 9.5 knots, I can't go over that rpm because I have a bad strut bushing that I'm replacing in this coming weeks and it vibrates a lot if I go over 1500 rpms.

My question is, he having more weight because of the fly bridge and having more pitch in the props, will 300 more rpms make you go 4.5 knots more?

 

[Bill Allen]

You don't mention engines size. I have 310 DD in mine at 1800 I'm probably not on plane trying, bow high and drinking gobs of fuel. So I slow down and go for the better fuel mileage. Everythings about horse power 310 just isn't enough to do that at least on my boat. I run 24x26 wheels. I'd wonder what his wide open RPM is? Bill

 

[Finalee]

Mine has 6v92's rated in the lower 400 hp range. Props are 26x26. It will run 16 knots tabs down at 1800 rpm. It takes 2000 rpm to get it on plane , she stays up to 1700 rpm. Top speed to date was 24 knots at 2350 rpm. She has a flybridge and Stabs.

 

[micky]

Forgot about the engines, they are DD 310n, on both boats.

 

[rob71]

Getting on plane and maintaining speed are greatly affected on my 43dc fly bridge , depending on how much fuel is in the tanks. Under 1/2 tank can do 20knts with 370hp Volvos. If over 1/2 lucky to hit 16knts.
Capt Rob

 

[rwappleton]

I have 24X23 4 blades. I plane about 17KTS at 1800 (6-71 390HP). I can do 22KTS any time I like and have never tried WOT. I do have a fly bridge.

I prefer to sight see so I run most of the time @1000 rpm doing 9KTS and averaging 1.5 NMPG. checked it today.