engine height

Burty

Senior member
Joined
Mar 31, 2004
Messages
6,347
Location
Weston Super Mare
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
 
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.
 
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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And you had better have a water pressure guage!
 
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?
 
[so just wondering where you run if its rough? [/B][/QUOTE]

In the container bay:banana: :drain:
 
Burty said:
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:dizzy:
 
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!
 
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????
 
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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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:D
 
Dude you know I'd claim salvage anyway
 
No you wouldnt cause I've moved me engine up three holes so I'd get there first :D
 
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