Correct Prop: Is it science or trial and error?

[technostingray]

I want to use my Power Cat 14 Foot Tri-Hull for recreation and skiing. The engine is a well used Inline 6 Merc alterenately identified as Mark 78A or a 700E The LU is serial number 1380217. The prop is a counter clock Brass that by my best estimates is 13 inches at the widest point. As far as 'PITCH' I am clueless. The first time out we had a payload of approximately eight hundred pound and maxed the tac. With the motor trimmed as we received it, it felt like we would go over backward but we could still get on plane. Trimming one hole farther from the aft got us on plane a litter quicker. The next time out the payload in the boat was about 650 but we were trying to get one 150 lb skier on two skies out of the water. Back to the drawing board. Anybody have anything to add. Considering the task, is there a pitch standard? In view of the load is there a combination of pitch and size that is better suited to the task? Thanks again.

 

[LubeDude]

Re: Correct Prop: Is it science or trial and error?

Are you really serious???

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

Originally posted by LubeDude:<br /> Are you really serious???

Is this a loaded question? I am serious about wanting to have fun with my boat. I could do without any acidic remarks, but even those are welcome.

 

[alden135]

Re: Correct Prop: Is it science or trial and error?

Have you read the walleyed prop post in the FAQ section? I'm finding it useful.

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

Originally posted by alden:<br /> Have you read the walleyed prop post in the FAQ section? I'm finding it useful.

No Sir. A link would be helpful. You know it is difficult to type under all this "medication" <br />:wink:

 

[Paul Moir]

Re: Correct Prop: Is it science or trial and error?

The "well hidden in plain veiw" Iboats FAQ Forum:<br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=forum;f=36 <br /><br />Waleyehed's is down near the bottom of the list. Good luck!

 

[achris]

Re: Correct Prop: Is it science or trial and error?

Originally posted by technosweeto:<br />

A link would be helpful.

You don't need a link, try looking in the FAQ section of this forum. You'll find it there.

 

[umblecumbuz]

Re: Correct Prop: Is it science or trial and error?

Fancy putting Walleyehed down near the bottom of the list!<br /><br />I vote he gets promotion.

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

Originally posted by achris:<br />

Originally posted by technosweeto:<br />

A link would be helpful.

You don't need a link, try looking in the FAQ section of this forum. You'll find it there.

Yes, achris I found it, all by myself. Am still looking for the meaning of atebis zulupa however.<br />I will see your "atebis zulupa" and raise you a have a nice day.

 

[LubeDude]

Re: Correct Prop: Is it science or trial and error?

Originally posted by LubeDude:<br /> Are you really serious???

Sorry, When you said that you were carrying an 800# load and that you were able to plane out quicker when you trimmed even more (should be the other way around, made me think you were pulling a leg or two.<br />Those old Brass Props were not that great, normally no cup and inefficient.

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

Originally posted by Paul Moir:<br /> The "well hidden in plain veiw" Iboats FAQ Forum:<br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=forum;f=36 <br /><br />Waleyehed's is down near the bottom of the list. Good luck!

Thank you Paul, I was reading it when the post were coming in. The conclusion I should arrive at is it is science plus trial and error, nes't pas?

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=36;t=000030 If there are others interested in the "science"

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

Originally posted by LubeDude:<br />

Originally posted by LubeDude:<br /> Are you really serious???

Sorry, When you said that you were carrying an 800# load and that you were able to plane out quicker when you trimmed even more (should be the other way around, made me think you were pulling a leg or two.<br />Those old Brass Props were not that great, normally no cup and inefficient.

I don't know what should be I only know what happened. Or, in this case what I was told happened. Back to the drawing board.

 

[Dhadley]

Re: Correct Prop: Is it science or trial and error?

Isnt testing a wonderful excuse....errrrr....reason to go boating?

 

[jjbuoni]

Re: Correct Prop: Is it science or trial and error?

You may wish to try this <br /> http://www.maxrules.com/propindex.html

 

[Dunaruna]

Re: Correct Prop: Is it science or trial and error?

Definetly science, to begin with - then trial and error.

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

Originally posted by Dhadley:<br /> Isnt testing a wonderful excuse....errrrr....reason to go boating?

"Absolutely"

 

[technostingray]

Re: Correct Prop: Is it science or trial and error?

Originally posted by sixers:<br /> You may wish to try this <br /> http://www.maxrules.com/propindex.html

Thank You