[mikesnowman]

Well, now that I am officially broke, I need to play the prop game. My 96 Z200 with 5.7l and alpha has a (repaired) 19p rapture prop. The top end on this thing with empty tank ( I actually ran out) is 49.8 GPS at 4850 rpm. I was hoping for a bit more as my old 96 Crownline with the 5.7lx and a 19 would do 54 and it was bigger and heavier. I know that all props are not the same. We tube with little kids a lot and really are not doing much else. I am wondering if I am better off going with a 21 3 blade or a 20 4 blade aluminum? I have no idea what the ratio of my drive is. I removed a large oblong washer form the bolt looking for a stamped ID but there was none?
Thanks in advance!

[indykoch]

Sounds like you have the right prop... your RPM's are right at the top of that engine's range. If you go up in pitch, you may only lose RPM and keep the same speed.

Are you hitting the rev limiter? What is the rapture prop - stainless? 3 blade?

[mikesnowman]

The rapture is a Michigan wheel pro. 3 blade ss . If I measure the thing from the center of the hub to the tip of the blade i get 7 inches. The prop says 14.25. On the highest speed run I had the tach was almost 5000. Just below. Just can not figure where the speed is.