260 prop question
#1
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260 prop question
hey guys i'm finally getting comfortable enough to run my boat in the upper end more often. i noticed now that i'm only getting 4400-4500 rpm out of the boat. it is a 375hp 496, its supposed to be good for 4800 i've. i'm running a 28"p 4 blade bravo, i was under the impression it was a 26"p. if i switched to a 26"p would this affect it the way i think? (extra 400 rpm and maybe a couple mph) also how would it affect midrange performance?
thanks in advance
thanks in advance
#2
Crazy Energy
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hey guys i'm finally getting comfortable enough to run my boat in the upper end more often. i noticed now that i'm only getting 4400-4500 rpm out of the boat. it is a 375hp 496, its supposed to be good for 4800 i've. i'm running a 28"p 4 blade bravo, i was under the impression it was a 26"p. if i switched to a 26"p would this affect it the way i think? (extra 400 rpm and maybe a couple mph) also how would it affect midrange performance?
thanks in advance
thanks in advance
Last edited by Velocity Vector; 09-15-2008 at 12:14 PM.
#3
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Yes, do try a 26p and compare to the 28p.
A labbed 28p will likely be the fastest but you may like the overall performance of the stock 26p better.
A labbed 28p will likely be the fastest but you may like the overall performance of the stock 26p better.
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Patrick
Patrick
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Crazy Energy
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A 26 P is actually a 25P 4800 RPM 14% slip shows 65 MPH 12% slip is showing 67 MPH
Your 28P is actually a 27P so @ 4400 RPM and 12% slip you should be going 66 MPH now and 68 MPH @ 4500 RPM
I would call a blade co and get the 28 labbed instead of buying the 26.
Your 28P is actually a 27P so @ 4400 RPM and 12% slip you should be going 66 MPH now and 68 MPH @ 4500 RPM
I would call a blade co and get the 28 labbed instead of buying the 26.
Last edited by Velocity Vector; 09-15-2008 at 03:17 PM.
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another member may lend me a 26p (thanks in advance bill!)....... my 28 is supposed to be lab finished (by merc. i guess).... i've gotten 68.1 on the gps with my current setup and the tach was at 4400.... i think i'm going to try the 26 and see how it changes performance....
thanks vec.
by the way how do you calculate this stuff?
thanks vec.
by the way how do you calculate this stuff?
#6
Crazy Energy
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another member may lend me a 26p (thanks in advance bill!)....... my 28 is supposed to be lab finished (by merc. i guess).... i've gotten 68.1 on the gps with my current setup and the tach was at 4400.... i think i'm going to try the 26 and see how it changes performance....
thanks vec.
by the way how do you calculate this stuff?
thanks vec.
by the way how do you calculate this stuff?
http://www.go-fast.com/Prop_Slip_Calculator.htm
If I can turn my 34P act a 33P @ 5800 and 12% slip I'm looking @ 106 MPH.
Last edited by Velocity Vector; 09-15-2008 at 03:53 PM.
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another member may lend me a 26p (thanks in advance bill!)....... my 28 is supposed to be lab finished (by merc. i guess).... i've gotten 68.1 on the gps with my current setup and the tach was at 4400.... i think i'm going to try the 26 and see how it changes performance....
thanks vec.
by the way how do you calculate this stuff?
thanks vec.
by the way how do you calculate this stuff?