Scarab 29 Top Speed
#1
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1997 Scarab 29, Twin 383 Mercuiser Mags (350HP each, stock), Bravo 1's with 23P Mirage props spinning out. I am only getting 65-66 mph @ 4,900 RPM's with drives out, tabs up. Shouldn't this boat be going faster? This model supposedly does 67-68 mph with stock 350 MPIs which I believe were rated at only 300HP vs the 350HP of my engines. Suggestions on getting more speed? Different props? I feel this set-up should be going 72-73 mph.
#2
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Bought the one out of NJ? Are the props Mirage, or Mirage Plus? Gear ratio in drives is 1.5? Yes, you should be able to run a bit above 70 with your power.
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If you have 1.5 drives your slip is at 7.2%
Getting your rpms up to 5200 with same slip you would be hitting 70 mph
Reduce slip to 5% gets you to just under 72 mph
Are the motors tired, have a lot of hours?
Getting your rpms up to 5200 with same slip you would be hitting 70 mph
Reduce slip to 5% gets you to just under 72 mph
Are the motors tired, have a lot of hours?
#4
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make sure your trim tabs are going all the way up the 29 scarab i had had a spacer in the cylinder and would not let the tabs come all the way up put a straight edge on bottom of the boat to the tab and check that way and i can tell you a 2 or 3 inch shorty will really wake that boat up as far as ride and speed
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Yes, I got the boat from NJ I was looking at. It's on Lake Norman now, in North Carolina, and will also be seeing time in Tampa, FL. I think the props are Mirage Plus but I'm not by the boat right now to 100% confirm. Drive gear ratio's I'm not sure. How do I check that?
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The motors should be good. They are 2012's and have about 180 hours. All cylinders were strong when tested during the survey.
Last edited by CLASSIC MUSCLE; 04-23-2017 at 06:49 PM.
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BTW are you reading the speed with a GPS?
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