08 yammer F250 prop question

Offroadr93

Cadet
Joined
Jun 27, 2013
Messages
9
I've got a 08 yammer F250 on my ranger 620 fisherman with a 15 1/2 in x 19p prop. My top speed with two guys and gear is only 51 mph and running wot at 5900rpm. I've been told this motor should be pushing a lot closer to 60mph. I have very good hole shot and I don't want to lose all of that but anyone running the same motor boat combo have a suggestion on prop pitch to get my boat more in the speed/rpm range it should be? Any help would be appreciated
 

jestor68

Commander
Joined
Jun 12, 2012
Messages
2,308
Boat Test has a test of a 2006 Ranger 620/621 powered by the Yamaha 250.

It achieved 55 mph @ 6000 rpm lightly loaded(just the driver).

They did not mention what prop was used. My guess is the Salt Water Series II 15.25 X 19 pitch.

I'd guess that you would get close to that by yourself.

It would be possible to prop it to get closer to 60 mph, but overall performance would suffer.

Besides, it's a well known fact that lots of folks like too overstate what their boat will do.
 
Last edited:

Offroadr93

Cadet
Joined
Jun 27, 2013
Messages
9
I have it on my yamaha phone app that when I put in my boat ,load, and motor with a 14 1/2x23 pitch prop it will push it 60.3 mph wot with two guys and gear. I should have stated that earlier as I don't read into people bragging at the ramp to much.... If I run this much pitch is it going to kill my hole shot?
 

jestor68

Commander
Joined
Jun 12, 2012
Messages
2,308
I wouldn't expect to drop only 200 rpm going from a 19 to a 23.

Keep in mind that all prop selectors are estimates. Actual on the water tests are what counts.

Is there some reason you skipped past a 21 pitch?

As far as hole shot goes; the more you lower the WOT rpm searching for another mph of top speed, the slower the hole shot is. You can't have it both ways.
 
Top