OK, what should I look at next?
10-16-2006 | 06:27 AM
#1
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Charter Member #927
Joined: Jan 2001
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From: IN
OK, what should I look at next?
I've got a 34' Super Hawaii with staggered 454 mags pulling about 425hp each. Untill my last time out ( for the season 
) I have been dissapointed with my top speed. I could only spin the engines to 4700rpm @ 67 mph. If I would trim my boat much past nuetral it would start to porpuse and I would have to drop the tabs to stop the porpusing. My last ride the water was perfect 18" chop, running into the wind with a light load. I was able to trim about 2 numbers above nuertral and run my tabs level. I hit 70.5 @ 4950-5000rpm 
.
I am running 25" Mirage Pluses. That puts me at 10-11% slip. Not bad for a 25* deep V. My props have been labbed. Should I be looking to tweek my props just a little more to get to 5200 WOT rpm? Or should I be looking at a set of Arneson rocker tabs so I can stop scrubbing of speed with the tabs?
) I have been dissapointed with my top speed. I could only spin the engines to 4700rpm @ 67 mph. If I would trim my boat much past nuetral it would start to porpuse and I would have to drop the tabs to stop the porpusing. My last ride the water was perfect 18" chop, running into the wind with a light load. I was able to trim about 2 numbers above nuertral and run my tabs level. I hit 70.5 @ 4950-5000rpm .I am running 25" Mirage Pluses. That puts me at 10-11% slip. Not bad for a 25* deep V. My props have been labbed. Should I be looking to tweek my props just a little more to get to 5200 WOT rpm? Or should I be looking at a set of Arneson rocker tabs so I can stop scrubbing of speed with the tabs?
10-19-2006 | 07:06 PM
#4
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From: Princeton, Wisconsin
Re: OK, what should I look at next?
You are probably at the correct rpm in the 4900-5000 range. You will need a dyno sheet to get the ultimate answer.
You are running quite well.
Have you experimented with # of blades or rotation?
You are running quite well.
Have you experimented with # of blades or rotation?
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Brett Anderson / BBLADES Professional Propellers
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Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
10-20-2006 | 07:01 AM
#5
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Charter Member #927
Joined: Jan 2001
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From: IN
Re: OK, what should I look at next?
Peak HP is probably the same range as the Merc 420/454. Engines have not been dynoed.
I tried a set of 24 Hydromotives , but they droped the bow a lot.
I would like to get rid of the calm water porpuse. I have already removed a slight hook that was in the last 4" of the hull.
I tried a set of 24 Hydromotives , but they droped the bow a lot.
I would like to get rid of the calm water porpuse. I have already removed a slight hook that was in the last 4" of the hull.
10-20-2006 | 08:45 AM
#6
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From: Princeton, Wisconsin
Re: OK, what should I look at next?
Hydro's aren't the right props for the boat. Have you tried Bravo 1's?
What about the rotation?
We have test Bravo props if you want to try them.
What about the rotation?
We have test Bravo props if you want to try them.
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Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
10-24-2006 | 07:10 AM
#8
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Joined: Jan 2001
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From: IN
Re: OK, what should I look at next?
I have never tried messing with rotation. I've been a little leary about changing the low speed handling handling. It's bad enough with the staggered engines.
Julie, the Hydro was about 4700 rpm and 65 mph. That was at neutral trim. If I trimed higher it simply slipped more, no more speed.
Julie, the Hydro was about 4700 rpm and 65 mph. That was at neutral trim. If I trimed higher it simply slipped more, no more speed.
