New Prop for Mark 3 grand raid???

[ATVBing]

i am running a 14 pitch by 11 1/4 currently<br /><br />it is very quick out of the hole but lacks on topend<br /><br />I was thinking of going to a 16 pitch by 10 1/2"<br /><br />need some suggestions before i start wasting money<br /><br />thanks

 

[ATVBing]

Re: New Prop for Mark 3 grand raid???

oh yeah,,,the engine is a suzuki DT40 1987<br /><br />also running lifters

 

[SpinnerBait_Nut]

Re: New Prop for Mark 3 grand raid???

Welcome aboard ATVBing, let's get this to the prop questions and topic forum.

 

[walleyehed]

Re: New Prop for Mark 3 grand raid???

Need to know what max rated RPM is for that engine, and what RPM you're getting with the prop you have now...

 

[ATVBing]

Re: New Prop for Mark 3 grand raid???

not sure about either at the moment<br /><br />no tach,,,,whats the cheapest way to install a tach?<br /><br />Would it matter that it is on a 15.5' inflatable which weighs about 450lbs boat/motor

 

[walleyehed]

Re: New Prop for Mark 3 grand raid???

I prefer the "right" way insted of the cheapest route...<br />Now, you can install one yourself if you go by the instructions and get it wired correctly-not a big deal, I'm sure you can handle it...<br />I can't even begin to guess at a prop with nothing to go by but weight and length...too many variables left unanswered.<br />I also have found OEM gauges seem to cost less in the long run.....hint, hint..

 

[ATVBing]

Re: New Prop for Mark 3 grand raid???

please elaborate on these variables that you need to know<br /><br />as far as a set of guages,,,,it is a bit overkill for my zodiac IMO. No place to mount the guages,,,and no need really. I wouldn't mind a temporary tach to get it dialed in, but that about it.

 

[walleyehed]

Re: New Prop for Mark 3 grand raid???

A Tachometer is the single most important gauge you can have or need. If we're not running the engine in the upper part of the recommended range, we will shorten the life of the engine considerably, as well as use more fuel than needed, and perform poorly.<br />The Variables are the boat, the engine, the current prop and how many RPM does "x" engine on "x" boat turn "x" prop.<br />If you have no use or intention of keeping your engine running up to par, send it to me....if it's worth anything to you, put a tach in or get a tiny-tach at the least. It's the only way anyone on this forum could rightly recommend a prop that would be close to what you need.<br />That tach tells you all you need to know about what that engine is doing...far from overkill.

 

[ATVBing]

Re: New Prop for Mark 3 grand raid???

thank you!<br /><br />A tiny-tach is about all i would have room for.<br /><br />I think my context is being a bit misleading and/or misinterpreted.<br /><br />I now understand the importance of a tach,,,thank you.<br /><br />So, is it possible to tune my speed with a prop,,,or am i limited to the equation you presented? What is the difference between a 2, 3 and 4 blade prop?<br /><br />What is gained or lost in prop diameter vs blade pitch? <br /><br />Could you recommend some good reading about the subject?<br /><br />again,,,,thank you

 

[walleyehed]

Re: New Prop for Mark 3 grand raid???

If you'll go to the top of this page in the left hand corner, there is a "propeller help" area with several subjects to click on.<br />In the FAQ section of the forums, there is also an explaination of some of the most asked questions about props...there may be something there that might help with some understanding as well. I think you will find most of the questions you have will be answered in those areas...if not, feel free to ask away...