Correct prop ?
08-30-2004, 08:47 AM
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Correct prop ?
I have a 98 29 scarab twin 350 mpi's and bravo 1's. Hooked up the gps yesterday at 4900 rpm's 67.8 turning 23p mirage plus's......is this all there is.
08-30-2004, 08:53 AM
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Re: Correct prop ?
you could most likely get more HP at a higher rpm. I would think small blocks would like turning at least 5200,prob max hp much closer to 6k if you want to push them hard(what is Merc's max on that motor?). Maybe try a 21" or lab your 23.
08-30-2004, 11:45 AM
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Re: Correct prop ?
I would try having the 23 bumped up to a 24 pitch add cup and lab finish.I would bet this will put you in the 4,800 rpm range and pickup the speed along with the mid range accleration.
08-30-2004, 01:43 PM
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Re: Correct prop ?
Your speed isn't bad considering the power, if the motors are stock. Your rpm is in a good place, a touch higher and you may see a little speed. But for the most part you are at about the max speed for the boat/power combination.
It depends on what you want from the boat. If cruise speed is important to you leave the props the way they are.
If you want a little more on the top end there is some work that can be done to the props that may give you a little more. You will lose some cruise speed if you were to have your props lab finished for top end.
There are many other considerations that have to be taken into account before I could reccommend what may work best for your boat.
Matt
It depends on what you want from the boat. If cruise speed is important to you leave the props the way they are.
If you want a little more on the top end there is some work that can be done to the props that may give you a little more. You will lose some cruise speed if you were to have your props lab finished for top end.
There are many other considerations that have to be taken into account before I could reccommend what may work best for your boat.
Matt
08-30-2004, 04:54 PM
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Re: Correct prop ?
You are about right for what you have, I have the same setup.
Let Darin do the props, he did mine and I am very happy with the work.
No fuel, no gear down river with a tail wind 69.3 @ 4800, small amount of prop work by cheap local shop.
No fuel, no gear down river with a tail wind 71.3 @ 5000, after Darin worked on them. T would not hold it there but that was the fastest I could get 71.0 and hold it there, I had to trim a little more with no tab and would pickup a little more and then porpoise some.
The best things is that at 3200 rpm I picked up 3 mph.
Let Darin do the props, he did mine and I am very happy with the work.
No fuel, no gear down river with a tail wind 69.3 @ 4800, small amount of prop work by cheap local shop.
No fuel, no gear down river with a tail wind 71.3 @ 5000, after Darin worked on them. T would not hold it there but that was the fastest I could get 71.0 and hold it there, I had to trim a little more with no tab and would pickup a little more and then porpoise some.
The best things is that at 3200 rpm I picked up 3 mph.
08-30-2004, 05:05 PM
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Re: Correct prop ?
if you dont mind me asking what did he do and what was the cost ? i'd really like to get a 4 blade on there for that mid-range kick-in-the-a$$
08-30-2004, 05:09 PM
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Re: Correct prop ?
You don't want a four blade on a 29 scarab, they don't seem to work well. Darin did the accelerator design, changed the low side pitch to eliminate a 3000 rpm blowout problem I had and labbed them. Can Darin for prices.
