ORIGINAL: RSABY50
Thanks guys for your answer, at this moment I tried only an 18x8 on my sv26, the plane is a high wing of 84 inches and a lenght of 63 inches, the max rev I got is 6200 0r 6400 rpm at the full throttle, but nothing change from 60% throttle to 100%
In my hand now I get a 18x6 and 16x8, so I should try the 18x6 first?
There is a big difference in props going from a 16x8 to an 18x8, in the the two brands I've looked at anyway. I have the same engine as you and was recommended to use the 16x8 first and then the 18x8, both Bambula props. I broke the 16x8 and just put the 18x8 on and test ran it. Didn't tach it, but after readjusting the needles, I could tell the rpm was down. The engine also was getting hot. The 18x8 is not only longer, but wider. It's even thicker at the hub. I'm not even going to fly the plane with it. The 16x8 was perferct for the plane which is a Goldberg Ultimate. The differences between the 16" and 18" props were apparent in the Zinger brand also. The 18" props had bigger hubs, wider blades and therefore, weigh more. Use the 16x8 and you'll be happy.
Rich, that looks like a good mod. I might have to try it out.