Re: Hwsiii :Going from aluminium to stainless
Les, theoretically you could have a 17" and a 19" pitch aluminum prop turn almost the same RPM, but there would have to be major blade geometry differences. In my opinion in most cases this would not be true. I would like to see pictures of the two props, but I believe that both props are probably closer in pitch than is posted on the props or there are other problems motor or tach that are creating this. I cannot make an informed decision when the very mathematics I depend on to get close are not in agreement with what is theoretically happening already. In theory there should be a difference of about 650 RPM between a 17" and a 19" pitch in the same make and model of prop. And if these props are showing right at the same speed at theses RPM it only reinforces the theory that they are almost the same pitch, at least theoretically or their is another problem.
BUT if you want to go ahead and buy a new SS prop anyway I would try a 19" pitch.
H
