Just a heads up too all, the other day I was able too thread one of the cheap thai longtail cast aluminum props with 3/4 ten thread sold on ebay and I think there is enough hub left to keep its integrity and strength. The size was 8.5x6 and from the looks of these props they look to be between a surface piercing blade type and a traditional longtail. I believe I paid 17.99 for it on ebay but have yet to try it because my sd build was spot on and think I will be going backwards at this point. Currently running a 9x6 back water on 6.5hp build. Might be a cheap solution for those in the testing stages to get dialed in on prop selection before there expensive true stainless mud motor prop purchase. I think on ebay the biggest size they offer is 8.5x6 but if you do a search on mudauber longtail you are able to get some some in the 10 inch range for the cheap or even higher possibly if you call them. I try to help when I can but remember these props are cast aluminum and not very durable but might help get people in the ball park. Any thoughts?

Why waste the $17.99 when there is ample threads and info now on lower hp sd builds. Plus if you build a sd and "dial it in" with this prop, you will not be able to get a stainless one like it. Plus if you using a backwater prop, you have a shortail mm not a sd, being their props are not sd props. So maybe you need to "dial in" a sd prop on your shorty. There are sd props for these size engines available. If I was to build one from scratch, I would get the sd propeller others are running, say the Hill 9x9 or even a Hopkins, then build my gearing around that.

Just an idea and you are correct but not everybody has 200 plus dollars laying around for a sd prop if they just need something to get there boat moving again, just commenting that I was able to thread one of these props with 3/4 10 thread. Next prop for me probably will be a hill marine 9x9.

i have a 15hp honda i am wondering what size prop would be the best. i also was wondering whats the best bushing material for my pipe? would i get away with 3 bushings?

3 busings made of bronze. Check out Go Devils' website.