1988 Bayliner Cobra 2250
22' with 260HP OMC Cobra I/O
Book says 4200-4600 WOT RPM.
Been using a older Merc High Five Prop. 13.5" x 17 pitch. GPS'd @ 48 MPH @ 4700 RPM WOT.
Wanted to do some river running so I looked into an aluminum prop. I ended up buying a Turning Point Hustler 3 blade Alu 14.25" x 21 pitch. Running it on the river/lake I got 50 MPH GPS @ 4150/4200 RPM WOT. I was expecting more? (it felt faster than 50, but car GPS doesn't lie...) Hustler prop probably half the weight the high five is, but going up 4" of pitch my RPM may have dropped too much to gain the speed I thought I would? (tho, 5 blade vs 3 would offset that a bit) Was doing a lot of reading before I bought the hustler, but running it was the only way I would know for sure...
If I went to a Hustler 14.25" x 19 prop, theoretically I would gain some rpm (300?), so I would be back to the higher end of the recommended RPM range (where I would like to be)
Would I gain any speed with the 19 vs the 21, or would I just get the engine to run in a happier range? (4500ish)
Any input is greatly appreciated!!
PS - Only downside is I chipped the prop on the first use in the river, so I can't do the exchange program through turning point, but oh well, live and learn.
22' with 260HP OMC Cobra I/O
Book says 4200-4600 WOT RPM.
Been using a older Merc High Five Prop. 13.5" x 17 pitch. GPS'd @ 48 MPH @ 4700 RPM WOT.
Wanted to do some river running so I looked into an aluminum prop. I ended up buying a Turning Point Hustler 3 blade Alu 14.25" x 21 pitch. Running it on the river/lake I got 50 MPH GPS @ 4150/4200 RPM WOT. I was expecting more? (it felt faster than 50, but car GPS doesn't lie...) Hustler prop probably half the weight the high five is, but going up 4" of pitch my RPM may have dropped too much to gain the speed I thought I would? (tho, 5 blade vs 3 would offset that a bit) Was doing a lot of reading before I bought the hustler, but running it was the only way I would know for sure...
If I went to a Hustler 14.25" x 19 prop, theoretically I would gain some rpm (300?), so I would be back to the higher end of the recommended RPM range (where I would like to be)
Would I gain any speed with the 19 vs the 21, or would I just get the engine to run in a happier range? (4500ish)
Any input is greatly appreciated!!
PS - Only downside is I chipped the prop on the first use in the river, so I can't do the exchange program through turning point, but oh well, live and learn.