Prop tune

[Mike Nelson]

Hi guys,



I have a 05 Nitro 640 with a 90HP Opti. I am currently running 45Mph at 5750rpm, i am spinning a 20P Laser 2. I find with this setup my engine over revs quite easily. I tried a 21p Trophy plus but found it was too much for the setup, rough idle, major jump in fuel usage etc.



Basically i wont a little more top end but i think a 22p laser 2 may be too much prop. Is it worth getting a little more cup put into my existing 20p laser 2? Will this mainly give me better holeshot or gain that little extra top end i am after?



I am also ruinning large vents in the prop should i drop these down to mediums as the engine revs too 4500-5000 on hopeshot.





Anyones thoughts.. Thanks

 

[byron cooley]

Raise the motor and go with the 22 - it will turn it without a problem.

 

[Gilbert Scales2]

I have a 1995 Nitro 640. I have a Merc (Not Opti.) 2002 90 hp. I have a 22P Laser 2 prop, I turn 5800 WOT 46mph. I do have a 6" jack plate, but find it makes little or no difference. I was thinking about a 4 blade, but everyone says it will slow me down WOT. Guess what I am trying to say, on these little boats, motors performance wise there isn't much we can do except spend money. Maybe someone has an answer, but not me. Keep the money and buy baits, rods, reels.



Bubby

 

[TritonGlenn]

Everyone wants a "little more top end" and "a little better hole shot" - even guys that have everything wrung out of their setup still want a little more. :lol:



Truth of the matter is, you're probably getting most everything you can out of that rig at 45mph. You "might" get a mph or two more out of it - depends on how much money you are willing to spend to get it. Most inexpensive way would be to add a little cup to that prop - probably will bring your RPM's at WOT down a hair, and you might see a mph or so increase in speed, but it ain't like you are going to jump up in speed by a lot.



I'd also agree with Byron that you can probably turn a 22 if you go up with your engine a bit. However, that's dependent on your water pressure too. If your water pressure is fine now, I'd go up a bit with your engine with your current prop to see if you can maintain that water pressure, and if so, slap a 22 on there and see what performance is like. More than likely, your MPH will come up, and the hole shot "might" be a little worse due to the larger pitch. Note - that's only a "might".



If there is one thing I've learned over the years - there is no perfect prop for every boat/motor combination. You can get close by going by what other people use, but how your boat is loaded may affect your overall performance. Altitude and other factors play into it as well. If you load heavier than most, you may have to run a lower pitch prop. If you run lighter than most, you may have to run a higher pitch prop.



Last but not least - yeah... change out your PVS plugs and see if that helps. That's a huge amount of revving to be doing at holeshot, so I'm not sure if just changing the PVS plugs will do the trick, but it's the cheapest beginning solution. More than likely, a change in prop pitch to that aforementioned 22 will get you where you need to be on holeshot. If you want to try the PVS route first - I'd get solid plugs and run those to begin with. If it needs more, drill out the plastic with a cordless drill that you bring with you on the boat when you test. Keep going up in hole size slowly until you tweek it. I no longer buy small/med/large plugs - just solids and then I drill them to the size I need. Saves money in the long run, and you aren't stuck with a whole bunch of different sized plugs when you are done.



All the best,

Glenn

 

[fatrap]

Bitten by the "speed bug" are we? The itch will never leave.

fatrap

 

[Jimmy Easterling]

I spent about $800 trying to get mine up and only increased 2 mph. I wish I had the $ back, it just wasn't worth it.