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Old 07-11-2004, 07:29 PM   #1
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engine height

whats the optimum engine height for speed in relation to the bottom of the hull if you have a bullet box and a et prop
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Old 07-11-2004, 07:32 PM   #2
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just wondering because if i raise my engine as high as it will go on the power lift the bullet is level with the bottom of the hull. i was just wondering if you would go any faster if it was even higher.
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Old 07-11-2004, 09:22 PM   #3
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A bullet even with the bottom of the hull results in a surfacing propulsion system.

Experimentation will determine the optimal height. If your gaining revs but not speed, you're too high.
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Old 08-11-2004, 08:59 AM   #4
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And you had better have a water pressure guage!
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Old 08-11-2004, 07:00 PM   #5
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yep got a water pressure guage.
spent ages reading posts on S + F last night it seems they think that the height for optimum speed is between 1" and 1 1/2" above but i'm worried this may be a little high.
my jack plate has approx 6" of travel so just wondering where you run if its rough?
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Old 08-11-2004, 07:31 PM   #6
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[so just wondering where you run if its rough? [/B][/QUOTE]

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Old 08-11-2004, 09:55 PM   #7
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Quote:
Originally posted by Burty
spent ages reading posts on S + F last night it seems they think that the height for optimum speed is between 1" and 1 1/2" above but i'm worried this may be a little high.
How much setback have you got?
Most people on S&F with your style hull run miles of setback, like 2-3' on some of the progressions. This extra setback puts the prop deeper in the water as the boat runs at an angle not flat, so you have to go higher on the jackplate to compensate.

Well thats my interpretation of it anyway
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Old 08-11-2004, 11:18 PM   #8
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We run about 8" setback plus a Stainless Marine lifter but the height varies from hull to hull - get a GPS and watch both that and the water pressure guage - if the boat starts going sideways or you start loosing water pressure, or it starts gong slower get it down and fast!
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Old 08-11-2004, 11:20 PM   #9
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got 7 1/2" of setback.
just trying to set it up so if its real flat calm i can go for it but don't want to loose the handleing when rough
i.e if i can go 1" above it will only go 5" below but is that enough????
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Old 09-11-2004, 08:36 AM   #10
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Burty why are you asking questions that you already know the answer to.
3" below pad is more than you will ever need for rough conditions
As for optimum height 1-1.5" above pad is going to take some holding on to....be very careful.
Seems like you are changing your spec all the time, you told me that you wanted the engine high for trailering.

Go to short shaft, better handling on a P20
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Old 09-11-2004, 12:54 PM   #11
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Quote:
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3" below pad is more than you will ever need for rough conditions
Red's about 3" below the pad and its mint in the rough
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Old 09-11-2004, 06:12 PM   #12
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wy duz dat bote dryver inn de pikk av a orinj catt kennil onn iz fkin hed

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Old 09-11-2004, 07:20 PM   #13
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I thought it was a spud croquet placed cunningly in the forground
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Old 11-11-2004, 04:14 PM   #14
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Dude, u know i wana go faster than u.
if it means running 1 1/2" above and hanging on for grim death then i'll do it. spose i'd best pay you for the work before it ends up at the bottom of the sea though a
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Old 11-11-2004, 04:15 PM   #15
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Dude you know I'd claim salvage anyway
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Old 12-11-2004, 12:13 AM   #16
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No you wouldnt cause I've moved me engine up three holes so I'd get there first
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