Piranha vs. aluminum

ricksrster

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Jun 19, 2005
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How does Piranha compare to same size prop made of aluminum? is it lighter?
 

walleyehed

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Re: Piranha vs. aluminum

I ran some piranha's....yea, they are light...<br />If you sneeze, you may shear a blade...<br />They had very good over-all performance compared to aluminum, but if ya ever hit anything, if you're lucky, you'll only have to replace 1 blade, insted of 2.
 

ricksrster

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Re: Piranha vs. aluminum

Thank you. I am going to try a 13.75 x 15 on my Mercury 850 to raise the RPM a little. I am using a 13 x 17 now with about 4600 RPM WOT.. On a good day it gets almost 4800 RPM WOT. I should be between 5000 - 5500 RPM. I've been looking at Black Max, Vortex, and Amita 3, Aluminum.
 

Texasmark

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Dec 20, 2005
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Re: Piranha vs. aluminum

Keep in mind, that weather has a big part to play in your overall performance. I know cold air is more dense, and the denser the air the bigger the bang per unit of measure of air, but I have read where 2 strokes like it dry too. Like your best performance will be on a cold day when a norther blows in with 20% humidity. Got that off this site mind you.<br /><br />That is contrary to what I know about combustion and dense air which is high humidity air; not dry air. But I will agree on the cold air.<br /><br />So, gotta sort the BS from the facts.<br /><br />We used to water inject jet engines on KC 135 aircraft on take off with a full load of JP4, to get the density up to get higher thrust so the sucker would get the wheels up B4 they ran off the runway.<br /><br />Some after market companies sold water injectors to put water into the combustion chambers of auto's to get the hp and mileage up back in the '70's.<br /><br />Everyone knows that you can get more hp from your mil at sea level where the air is thick and wet as compared to the rocky mountains where it is dry and thin.<br /><br />I dunno, I just loaf for a livin. Retired.<br /><br />So, when you are evaluating your performance, keep maw nature in mind.<br /><br />Mark
 

walleyehed

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Re: Piranha vs. aluminum

We used to water inject jet engines on KC 135 aircraft on take off with a full load of JP4, to get the density up to get higher thrust so the sucker would get the wheels up B4 they ran off the runway.<br />
The water, water/alcohol injection did not produce more power...It cools the T4 temp, so more power can be applied, as the turbines are temp-limited.<br />Most power in any engine is dry, cool air...if you start adding moisture, the density of air is less. The higher the humidity, the less power you have.
 
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