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Old 11-24-2016 | 02:32 PM
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Default Scarab 29 raise engines?

I have a 97 Scarab 29 twin 350 MPI with bravo 1s. Doing some transum repairs over the winter and a re-power to 383. While im into the transum I am thinking of raising the engines up +3" Current prop shaft centers are 7 3/8 from the bottom.

I have been reading up and educating my self as much as possible...but Im still looking to make sure I am going the right direction. Any tips, thoughts, or theories welcom.

Thanks
AJ
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Old 11-24-2016 | 03:37 PM
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Definitely do it. I don't know if I Would go up 3" but 2" for sure.
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Old 11-24-2016 | 05:14 PM
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If i found that i went up too high...do i the ability on a stock bravo 1 application to space the lower back down?
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Old 11-24-2016 | 09:44 PM
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It's easy to go down with spacers. I would go up the 3 inches. You will probably have to go to a different prop. Just remember about engine height and the exhaust outlets. IF you go too high you might run into clearance problems.
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Old 11-25-2016 | 12:55 PM
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Originally Posted by scarab29aj
if i found that i went up too high...do i the ability on a stock bravo 1 application to space the lower back down?
yes you can put spacers on your drives if you have bravo drives. The other thing going to high changes the center of gravity and can cause issues 3" inches should be okay. The lower the engines in the boat the better the handling. Ideally if your not worried about $$$ i would put imco -3 lower cases on.
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Old 11-25-2016 | 01:22 PM
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I agree with ^, put shorties on there and don't mess with the COG
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Old 11-25-2016 | 02:27 PM
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Good point on the center of gravity being raised...playing devils advocate, I wonder if having two engines could possibly cancel out some of the negative effects of the higher gravity. Just spitting that out there. Thanks for the thoughts!!
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Old 11-25-2016 | 03:36 PM
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I'm no engineer, but raising the height will increase a pendulum effect of heavier motors higher up
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Old 11-25-2016 | 04:09 PM
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my engines are raised and had +3 imco boxes on it, prop shafts were level with the bottom, and would not get on plane, 1 inch spacers would get up on plane if I surfed my wake or feathered the throttles back and forth and I saw 87mph once. put 2 inch spacers on and hopped right on plain with satin finished props. and hit 87 mph every time I tried WOT. however it dances somewhat at that speed and if the engines were lower in the engine compartment it would not chine walk as much. so now I have it where the propshafts are 3 inches below and can go down an extra 2 if I need too.
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Old 11-25-2016 | 04:34 PM
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three to four inches below is kind of the sweet spot with SCARAB's. My 34 was at 4 inches I think. Stepped hulls can usually run higher. SCARAB's need bow lift.
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