Will a different prop solve my problem

[rabiddawg]

I have searched thru threads and have not found a solution to my problem.

I recently bought a 03 Rinker 192 Captiva with a 5.0 Merc. It came with a 14.25"x17 stiletto ss prop and I get 4950 rpm and 45 mph (gps) trimmed up. The boat pulls ok, but will not stay on plane below 3k rpm and about 24 mph. For tubing and skiing it is fine but for wake boarding I would like to be able to stay on plane a bit slower. The prop shop guy says I have a good prop but the application is wrong; he wants to sell me a Mirage 19p for $525 (keep dreamin')

Do I need another prop or do I need to add trim tabs?

Thanks.

 

[QC]

Re: Will a different prop solve my problem

Do I need another prop

The short answer is yes, but only because you should always have a spare. Sooooo . . . you might want to try something different for that, and I am sure you'll get some help here. I would not expect any major change in your planing speed though, small difference? Possible, but nothing that will magically make it a good wakeboard combo.

I need to add a whale tail

For me? Never.

trim tabs?

For me? Always! I prefer helm adjustable, but even Smart Tabs will bring your planing speed down below 20 MPH. My 23 footer will plane at 13 MPH with tabs full down. Much easier to control wakeboarding type speed.

 

[rabiddawg]

Re: Will a different prop solve my problem

Thanks, QC.

I have two extra aluminum props that came with the boat. The previous owner put the stiletto on and said it was much better than the others. I intended to run the other two but forgot to take the splined piece with me last weekend :redface:.

I just looked on West Marine's site and they carry the smart tabs so I think I will put a set of those on for this weekend. It sounds as if they may fix my problem.

 

[QC]

Re: Will a different prop solve my problem

The trick to Smart Tabs is to move as much weight aft as you can. This may allow you to trim higher and that difference could get you some more top speed. Can you make her porpoise now with trim at full speed? If so, the tabs will solve that.

 

[rabiddawg]

Re: Will a different prop solve my problem

Yes it will porpoise.

The smart tabs should be in today. WM had to order the ones for my boat; the ones he had in stock were for a smaller boat.

 

[captkevin]

Re: Will a different prop solve my problem

Another improvement to lower planing speed is to go with a 4 blade prop vs 3 blade. 17 pitch seems awful low for a 19' with a 5.0 motor - what drive ratio do you have?

 

[junior1113]

Re: Will a different prop solve my problem

id put a 17p 4 blade on will drop a little rpm as you are pretty high now this combined with tabs youll be fine

 

[rabiddawg]

Re: Will a different prop solve my problem

Drive ratio is 1.62.

The prop guy said the stiletto is a good prop, but the wrong application in my case. I am guessing the stiletto is designed to be an all around prop and I need something with a different blade geometry that will give more hole shot bite.

With the stiletto, it pulls fine for me. I just hope the smart tabs give me what they claim. If I can knock 9 mph off the plane speed everything will be perfect, I think.