Purchased a PYI 16" 3 blade prop with a recommended pitch setting of 22 degrees for a 2001 Hunter 340. The boat is not able to reach its max PRM rateing of 3400. Best we can do is 2900 RPM, or a difference of about 15% of Max. This would suggest that I need to move to a lower pitch of 20 degrees. Can anyone confir that this is the correct pitch for the above boat.
- Status
Yep - 2 and maybe even 4 degrees
Have a two blade maxi on a 340 . . .original was 16x13 suggesting a 24 Degree pitch on the two blade maxi. First year I used the 24, too much. Last year 22, still too much. Could not get above 2700 rpm without smoking. Some guy on HOW originally told me to drop it 4 degrees, and I didn't believe. This year it will be a drop of 4 degrees and it probably will be right. Depending on your current max rpms at 22 degrees, I would set it at 20 or 18 . . . for your 3 blade. But by all means drop it 2 degrees this year. Jim
Have a two blade maxi on a 340 . . .original was 16x13 suggesting a 24 Degree pitch on the two blade maxi. First year I used the 24, too much. Last year 22, still too much. Could not get above 2700 rpm without smoking. Some guy on HOW originally told me to drop it 4 degrees, and I didn't believe. This year it will be a drop of 4 degrees and it probably will be right. Depending on your current max rpms at 22 degrees, I would set it at 20 or 18 . . . for your 3 blade. But by all means drop it 2 degrees this year. Jim
Suggest Contacting PYI Again
When I first put on my two-blade max prop the RPMs were low and after talking to PYI I bumped the pitch up one notch (the RPMs were only a little bit off). The smoking went away and this was about ten years ago. They really know their business and I'm sure they can help. The feathering prop was one of the best purchases I've made. Once you get the pitch nailed down I'm sure you'll like it too.
When I first put on my two-blade max prop the RPMs were low and after talking to PYI I bumped the pitch up one notch (the RPMs were only a little bit off). The smoking went away and this was about ten years ago. They really know their business and I'm sure they can help. The feathering prop was one of the best purchases I've made. Once you get the pitch nailed down I'm sure you'll like it too.
correct pitch
please post the results for the correct pitch and any rpm info you may have when you get it all figured out. I am thinking of putting a 3 blade on my Hunter 336(the same as your 340) or if you would be so kind as to e mail me the results at peterc53@aol.com Thanks!
please post the results for the correct pitch and any rpm info you may have when you get it all figured out. I am thinking of putting a 3 blade on my Hunter 336(the same as your 340) or if you would be so kind as to e mail me the results at peterc53@aol.com Thanks!
I would suggest 2 degrees
Dear Floyd, If you reduce the pitch by 2 degrees you will increase your Rpm’s by apx. 13% . This should put your maximum obtainable Rpm’s to 3,300. I would not suggest 4 degrees reduction. Sincerely, Kevin L. Woody
Dear Floyd, If you reduce the pitch by 2 degrees you will increase your Rpm’s by apx. 13% . This should put your maximum obtainable Rpm’s to 3,300. I would not suggest 4 degrees reduction. Sincerely, Kevin L. Woody
Results posted just after Memorial Day
I'll provide results after Memorial Day. Woody is probably right in that you are already at 2900. It isn't a killer if you don't reach max rpm and 2 degrees is safer. But tune in later this month for an update. I'll post it and send it directly to you. PYI is very responsive, but I'm not sure that their settings always take the difference between a sailing prop and a feather prop (surface area). the tables take your pitch and convert it to degrees for their props. There is no discussion or allowance for the slippage on the sailing prop when compared to the feather prop. Perhaps that isn't a factor, but the feather prop really takes hold in contrast to the sailing prop when one really wants power NOW. Thus it would appear that the feather prop is more efficient and doesn't need as aggressive a pitch as the sailing prop to accomplish the same results. Jim
I'll provide results after Memorial Day. Woody is probably right in that you are already at 2900. It isn't a killer if you don't reach max rpm and 2 degrees is safer. But tune in later this month for an update. I'll post it and send it directly to you. PYI is very responsive, but I'm not sure that their settings always take the difference between a sailing prop and a feather prop (surface area). the tables take your pitch and convert it to degrees for their props. There is no discussion or allowance for the slippage on the sailing prop when compared to the feather prop. Perhaps that isn't a factor, but the feather prop really takes hold in contrast to the sailing prop when one really wants power NOW. Thus it would appear that the feather prop is more efficient and doesn't need as aggressive a pitch as the sailing prop to accomplish the same results. Jim
Report 4 degrees off the table works for me
Launched the boat today. Got 3,000 without a problem and slightly more than 6 knots. Remember that I started with the 16x13 table suggested 24 degrees for my 340. Last year tried 22 and couldn't get above 2700 without smoking. This year its 20 degrees and seems to be working fine. I note that in 1999 the following was posted. I would have saved time by listening to that advice: Response to Max-Prop: max pro on 340 Submitted by capt. mike on 11/19/99 at 12:16PM regarding Hunter 34 I may have what you are looking for. Max prop on my 340 is one season old and used in fresh water only. Works like a charm at 20 degrees of pitch. Am selling the boat and moving up in size. E-mail me at mnhatton@adelphia.net if interested...capt. Mike Check the achieves . . . its all there. Jim
Launched the boat today. Got 3,000 without a problem and slightly more than 6 knots. Remember that I started with the 16x13 table suggested 24 degrees for my 340. Last year tried 22 and couldn't get above 2700 without smoking. This year its 20 degrees and seems to be working fine. I note that in 1999 the following was posted. I would have saved time by listening to that advice: Response to Max-Prop: max pro on 340 Submitted by capt. mike on 11/19/99 at 12:16PM regarding Hunter 34 I may have what you are looking for. Max prop on my 340 is one season old and used in fresh water only. Works like a charm at 20 degrees of pitch. Am selling the boat and moving up in size. E-mail me at mnhatton@adelphia.net if interested...capt. Mike Check the achieves . . . its all there. Jim
- Status