altitude

[malagaoth]

how does altitude affect prop performance? is it just that altitude the engine creats less hp?

 

[TELMANMN]

Re: altitude

I know altitude affects carburation but as to prop? I would think water density not much different high or low for a prop but then water boils at different rate's dependent on altitude.

 

[jt57]

Re: altitude

i dont think that altitude directly affects the prop's proformance.It affects engine proformance and that does affect the prop proformance.i boat at over 6600 ft in elevation,and have had to have the carbs on my o/b rejetted twice to get it where i wanted.But now if i go below 4400 ft i will have to have the jets in the carbs changed ,or i will stand a good chance of burning up the engine.

 

[Realgun]

Re: altitude

Basically you lose some Hp the higher you go.<br /><br />Lets say at sea level you run a 19 pitch prop turning at 5500rpm running the boat @50 mph. <br />The MFG Recommended RPM is....5500. <br /><br />Now you come to my lake in New Mexico @ 5000 ft.<br />Your motor turns 5000 rpm your speed has gone to 42 mph!<br /><br />So you down pitch the 4 inch to a 15 pitch to gain the recommended rpms. Your now running 5400rpm but your down to 45 mph. <br /><br />All due to altutude!<br /><br />Now you buy a Verado and forget all of the above as the Supercharger just throws altitude out the window!<br /><br />I also over think stuff too!

 

[TELMANMN]

Re: altitude

Didn't think about the supercharge aspect. Pretty good.