quick prop question *new Info*

[gtdavis]

I have an 18 foot Rinker 3.0 merc with a high five prop with 19" pitch. My numbers are ok WOT RPM runs a little high around 45-4700 top end only 36-38 my question is will a 3 blade lets say 21" pitch give me any better MPG Im not worried about losing hole shot we dont ski just tube a little on top end might be nice I know new my boat only ran 40-42mph so mostly looking at milege. thanks!!!
BTW I dont run it WOT right now lol

 

[180shabah]

Re: quick prop question

Re: quick prop question

High fives are really good props and typically swap pitch for pitch with a 3 blade. Adding 2" of pitch will pull your rpms down 400+ but will NOT give you a measureable increase in efficience. It WILL slow your holeshot, it WILL reduce midrange accelleration. It will also trim a little off your top end IF you can even still spin it to 4k+.

You need to prop for the TOP of the WOT range for your engine. There is nothing to be gained by propping for the bottom.

 

[gtdavis]

Re: quick prop question

Re: quick prop question

lol sounds like I just need to leave things alone then

 

[gtdavis]

Re: quick prop question *new Info*

Ok strange stuff!! Took the boat out today WOT trimmed out could run over 5k ???? No faster just higher RPM. Only thing I did was change the plug wires since last time I was out. Could I have been running on three cylinders??? Seemed to have more take off?? Anyway back to my original question about moving to a three blade with more pitch??

 

[180shabah]

Re: quick prop question *new Info*

OK - sounds like you do have "room" for more pitch. Did you have any specific props in mind? Coiuple of favorites around here:

Hustler - very aggressive three blade design with vented hub. eliminates blowout, good top end and decent hole shot - they are also developing a rep as being unpredictable. On boat that they work on - they are awsome, but on others they are not...

AMITA4 - four blade design fairly conservative that swaps pitch for pitch with a 3 blader. great holeshot (not quite highfive though) good slow speed cruising control and great midrange acceleration. Pretty consistant from hull to hull.

For your particular case I would suggest the amita. Might give up 1 mph on the top end, but the strong holeshot makes up for it.

 

[gtdavis]

Re: quick prop question *new Info*

Thanks 180.... no one particular in mind just trying to get the best bang outta my boat...I like the highfive out of he hole but I dont want to have to keep watching my RPM's (glad I did today though!) All I do is pull a tube and cruise. One thing I was running a little lighter today maybe MAYBE 100lbs would that have made that big of a difference in WOT come to think of it Ive ran even lighter Im just taken back when I looked down and was turning 5,100 RPM Ill look into those props!

 

[gtdavis]

Re: quick prop question *new Info*

Wow this is tough! I like the Amita4 but only found it in the same pitch I already have and dont wanna give up what little topend I have.... I dont have any local shops so Im gonna have to order online kinda worried Im gonna be stuck with a prop I dont like. I think between the two Im gonna lean towars the hustler but Im still gonna do a little research....any other suggestions anybody????

 

[180shabah]

Re: quick prop question *new Info*

Sorry, the speed loss I was referring to was compared to the hustler. I would expect both of the above mentioned props to be at least as fast on the top end as the highfive you are running now. The hustler just might be a hair faster still. But remember, this speed we are talking about is at WOT and you will very rarely run that fast anyway.

 

[180shabah]

Re: quick prop question *new Info*

One more thing to throw out - the Rubex4 is the same prop as the amita4, except it has the removable hub. If you decide on a different prop later, you can get just the prop and reuse your existing hub - saving $30-40. The price difference up front is only about $15.

 

[gtdavis]

Re: quick prop question *new Info*

Thanks!! I looked a little more into the Amita (found it 21") Im leaning that way because I do pull my kids on a tube and the high five does give me good low/mid power to whip it around I think I might loose too much of that if I go with the hustler. Im ok with my top end 35-38 is plenty fast I really dont care when guys fly by me and who knows how fast I still get where I am going. Im starting to agree Im thinking the Amita may be the better all around prop for what I do and Im trying to accomplish getting my WOT RPM down while not giving up any performance