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propeller help 1998 200 hp

I have a 21' trophy hardtop with a pod and a 1998 2 stroke 200hp merc.It currently has a alluminum 14 1/4 x 19 4 blade prop, I need to bring the rev's up at least another 800 rpm.Anyone have any suggestions?
Thanks
 
Re: propeller help

Has it always been running 800 rpm low? Be sure the tach is working the right way. So you are turning around 5000 rpm right now?

When was your last tune up? I have seen people throw money at props to change rpms and it was actually a motor missing on a cylinder or two.

Those 200 mercs are great motors and they will fly on the right hull. How much weight are you moving?
 
Re: propeller help

The motor runs perfect,I put the motor and prop on last year. Took a guess with the prop,the revs have allways allways been to low.As far as weight,not sure but it is very heavy
 
Re: propeller help

So am I to understand you do or do not have a tach? What was your old prop and rpms? Do you have your old prop? Was is running the same rpm?
 
Re: propeller help

Ran some rough number for ya. The rigged weight of your boat should be about 3500lbs (dry) - add fuel, people, a bit of junk - 4000-4300 lbs (rough guess).

Running a 200 horse with 1.87 gears (standard) the "theoretical" best prop to reach 5250 rpms (optimal WOT) would be a 3 blade 16.5 pitch.

Since there is no 16.5 pitch, a 16 or 17, 3 blade would be close.

Compared to what you are running now you would gain about 500 rpms with a 3 blade/17 pitch and about 700 with a 3 blade/16 pitch (keeping the diameter at 14 1/4 or 14 1/2).

There is a 15 1/4D 15P which would give you about 750 rpms more than present (all else being equal), that may also suit your needs - especially if you tend to run "heavy" (more than 1/2 tank of fuel and 2 or more persons on board "on average").
 
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