1st time out with new engines
05-25-2023 | 06:20 PM
#32
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From: West Michigan
05-25-2023 | 08:43 PM
#33
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From: pa
Just throwing this out there, on my 25' Nordic rage with a 496 HO, the boat ran constantly 73-74 @ 5100, best of 75 with a stock 26. I put a labbed 28 on it and it ran best of 78 @ 5000, this was also running CMI etops fwiw
Props were all bravo's in 1.50 ratio
my current boat spins stock 30's to 5000 and runs 83-84
I know there's countless variables here to consider, just putting some real #'s to different pitches in your rpm
Props were all bravo's in 1.50 ratio
my current boat spins stock 30's to 5000 and runs 83-84
I know there's countless variables here to consider, just putting some real #'s to different pitches in your rpm
Last edited by blownhammer2000; 05-25-2023 at 08:48 PM.
05-26-2023 | 08:17 AM
#36
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From: SW Ohio
First off....if the 28's work for what you want you could have them tweaked to help with planing if that's an issue
Second...I would not want the motor to live in the peak torque band...you are asking for drive issues IMO....that's a lot of stress on the drives at peak torque trying to push the boat to top speed.
Third...could always drop a little tab to help get on plane if needed.
As for everything else...if you are worried about hurting those motors at anything over 5K then you should seriously think about rebuilding them with better parts....I know we've been down the long horrifying road of your builds in other threads but to me any BBC that's built with anything better than stock parts should spin 5500+ all day long with ease....a black merc motor can do that with cast internals in some. I wouldn't worry about the motors personally if they were built and tuned right. If you are leaning out up top then you need more jet simple as that as I think I remember you being carb'd...can't remember at this point lol. Break them dudes in and let em eat!
If it was my boat I would prop them to run at 5500-6000 which would be probably about what you have and you'll still have the low end with smaller props and I'm betting higher top speeds...all about what you want out of the boat. Just my thoughts.
Second...I would not want the motor to live in the peak torque band...you are asking for drive issues IMO....that's a lot of stress on the drives at peak torque trying to push the boat to top speed.
Third...could always drop a little tab to help get on plane if needed.
As for everything else...if you are worried about hurting those motors at anything over 5K then you should seriously think about rebuilding them with better parts....I know we've been down the long horrifying road of your builds in other threads but to me any BBC that's built with anything better than stock parts should spin 5500+ all day long with ease....a black merc motor can do that with cast internals in some. I wouldn't worry about the motors personally if they were built and tuned right. If you are leaning out up top then you need more jet simple as that as I think I remember you being carb'd...can't remember at this point lol. Break them dudes in and let em eat!
If it was my boat I would prop them to run at 5500-6000 which would be probably about what you have and you'll still have the low end with smaller props and I'm betting higher top speeds...all about what you want out of the boat. Just my thoughts.
How much throttle did you have left when you hit 5000 RPM?
After we got our injector issue figured out, and we went to the pond, we were hitting 5100 RPM with a good third of throw on the stick. There was no way I was going to just stab it and see what happened. And I have forged internals. Not a chance. That was with a B1 26P. We were running 71MPH. I, too, had the thought that I might actually need a 30P, instead of a 28P. I found and bought a 28P, and it was perfect. 76-77 MPH @ 5000RPM with the run stick pegged.
I’d suggest going up one pitch increment at a time until you hit your desired RPM just as the sticks hit the pegs.
Thanks. Brad.
05-26-2023 | 11:52 AM
#39
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From: Cape Coral FL
You can pretty much tell how fast a Bravo boat is by the pitch of the prop. At least this is what I have seen on my own boats. How fast was it before? What pitch prop were you running? How much HP did you add?
This is with a 1.5 drive ratio
26" up to 70mph
28" 70-80
30" 80-90
32" 90-100
This is with a 1.5 drive ratio
26" up to 70mph
28" 70-80
30" 80-90
32" 90-100
05-26-2023 | 01:20 PM
#40
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From: West Michigan
You can pretty much tell how fast a Bravo boat is by the pitch of the prop. At least this is what I have seen on my own boats. How fast was it before? What pitch prop were you running? How much HP did you add?
This is with a 1.5 drive ratio
26" up to 70mph
28" 70-80
30" 80-90
32" 90-100
This is with a 1.5 drive ratio
26" up to 70mph
28" 70-80
30" 80-90
32" 90-100
