So... I buy a boat from Mississippi....

4WinnsH200SS

Recruit
Joined
Jun 2, 2010
Messages
5
And I live in Utah, with most of my boating at elevation. The Boat is a 2008 Four Winns H200SS with the Volvo Penta 5.0 GXi motor, 270 HP, Fuel Injected, with a 1.60 Gear Ratio. The prop is the original stainless Volvo Penta 14 3/4 X 19. I am told that the engine has a 5000 RPM max and most say it should operate at 4800 under full throttle. I di

On its first day on the lake I was able to get it to 40 MPH w/ 6 of us and a full tank of gas. When I put two small kids on a tube, I could not get the boat to plane. I was plowing at 10 mph- I did not get a tach reading at top speed, but I know I think it was well below 4000.

In terms of usage, I am going to be pulling kids on tubes and wakeboards and I don't think I would have any reason to go much over 40, but I would like it to get to that speed before I become an old man. :)

Here goes... I know I need a new prop. Do I need new gears? I have had one person tell me I should go to a 17 degree prop, and another dealer 15. I have also been told that a 15 is too small for a boat my size.

Any help would be appreciated! In advance, thanks!!
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: So... I buy a boat from Mississippi....

Welcome,
What rpm were you at at 40 mph? Prop size,max rpm and speed will tell us where your at.And give a closer idea what will help.Off the top of my head I would suggest a 4 blade 17" pitch.If we go from ss to al its difficult to predict exact results.
And without your present specs no way to predict rpm results.
 

4WinnsH200SS

Recruit
Joined
Jun 2, 2010
Messages
5
Re: So... I buy a boat from Mississippi....

Next time out I will get an exact number. I would say that at 40 mph I was turning 3900 RPM.

Max RPM is 5000, and I am told that WOT is 4800.

Thanks!
 

Leardriver

Petty Officer 1st Class
Joined
Oct 7, 2008
Messages
380
Re: So... I buy a boat from Mississippi....

That same boat in Denver at 5800 feet elevation with a 17 pitch 3 blade aluminum turns 4200 rpm lightly loaded, 4700 with a 15 pitch. a 17 stainless 3 blade is about perfect.
 
Top