06-21-2010, 02:53 PM #1
Speadfreaks impeller set back mod
Anyone had this done? Any gains over a standard repitch? I have a rude1 ski and need to repitch a 15/20 4 blade. I was thinking of doing it myself but it would be my first attempt at repitching a prop.
06-21-2010, 02:56 PM #2
06-21-2010, 04:41 PM #3
eric with speedfreaks repaired --repitched and did the set back on my impeller --went from a 15/20 to a 12/21.5 with the set back and it is doing great --staying around 8000 to 8100 rpms depending on the weather --i can't give you the gains because i was on the rev. limiter before that --i had 3 things done at once and eric did a super fast turn around
06-21-2010, 04:46 PM #4
06-22-2010, 06:01 AM #5
OK ...I'll bite, whats it suppose to do.
06-22-2010, 07:07 AM #6
06-22-2010, 07:30 AM #7
06-22-2010, 09:22 AM #8
- Join Date
- May 2005
putting the back of the blades tight to the pump veins is the same as having a tight impeller to wear ring tolerance - less blow by - if there is any air in the pump it will be pushed thru the veins faster in a single vein rather than cavitate between them. As they say in racing - every little bit helps - will you notice any gain? Too many factors to say. Go for it.
06-22-2010, 10:04 AM #9
Only thing is that if you have a real steep prop (like me) you cant do the set back. With a 24 or 25 pitch prop the blades are already very close to the stater. If you would machine the prop to move it closer it will hit the stater. But it will definatly work if you have a 22 or less pitch prop.
06-22-2010, 10:52 AM #10
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