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Hydra foil for my 99

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oldman

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I have johnson 9.9 outboard. I

I have johnson 9.9 outboard. I was wondering if a hydrafoil would help engine performance and stability my boat 16ft seanymph bt165 both boat and motor were made in 1991 thanks for your thoughts
 
"I have tried my boat with and

"I have tried my boat with and without the device...The advantage seems to be that the boat will plane off at a lower speed when the load is unbalanced. It is especially useful when I am out alone. The gas tank and the steering wheel are in the back and the foil helps to bring the boat onto a plane at lower speeds. If the load is balanced, I really don't see any advaatage...just my experience for what it's worth!"
 
"i dont know if it would help

"i dont know if it would help or not on a 9.9......seems like it would not work well without tilt/trim.

if you find out that it does let us know........i have a '72 9.8 merc and a '64 18 rude that i would like to get a little more out of.

i also have a '79 115 johnny and i install and remove my hydrofoil depending on where im fishing.

in the arkansas river below kerr dam the water runs swift sometimes and i get a lot of porpoising at cruising speeds and during deceleration---i was running it in the lake but it seems i get a faster hole shot and better fuel mileage without it................when i first got it i loved the way it held the bow down (especially when fishing alone in rough water)
then i got to thinking i had a fuel leak---its supposed to improve your fuel mileage and performance.........BS.......it seems to dig the bow into the water (seems like it has more draft or something with this installed) and at wot the dang thing is out of the water-----how is that supposed to improve top end?

now if you do water sports i would recommend one......otherwise i would stay away.

just my 2 cents.......you know what they say about opinions?------they are like a**holes, everyone has one and most of them stink.....lol.

sad thing is when i first got it i would have recommended one for everyone.......now i feel like ive wasted $50.........hopefully when summer comes and i play as much as i fish my opinion may sway a little."
 
i think if you are running thi

i think if you are running this boat with just you in it and using a tiller handle on the engine and the boat is rear loaded with gas etc it may help you a tad with coming on a plane...loading the boat to the front will do the same thing....i run one on a 17 foot 100 gauge bass boat with a 88 evinrude...waste of money..no way i would use it on a boat without power trim with a decent size motor...the only reason i would buy and install one on you rig as described is if i though it was a safety problem taking too long to come onto a plane..i dont like to stay in the hole too long for vision reasons if around possible traffic..i would try moving cooler etc forward in boat first..
 
"I do a fair bit of "riggi

"I do a fair bit of "rigging" and have tried out most products that are on the market that promise to improve this, that and everything else - because inevitably someone will ask and I like to say "ya, I tried that and this is what I observed".

I ran a doelfin on both my 9.9's and 15 horse pushing a 14 1/2' Princecraft over the course of two summers - both off and on in different situations to see what they did for performance.

It worked well keeping the bow down in canals (where I run alot) that have a 7 mph speed limit - not really on plane at that speed, but kinda "jacked up" the transom (unfortuanately no way to measure how much extra stress that put on the motor, brackets or transom itself).

Outside of that narrow use, I found that contrary to what the claims on the packaging said - there was no increase in speed, no fuel savings at all and fiddled with a stop watch to try and gauge time to plane, but seriously, this is a "little boat" with a "low horsepower" motor, what's really the difference between 6.2 and 7.1 seconds. (speed comparible with/without via gps - fuel was simply tested over the same distance with and without - ya not totally scientific, but as close as you get with a very small motor)...

I did find that it made the motor alot more difficult to turn - likes to go straight all the time. And it does put tremendous stress on the cavitation plate.

That doesn't seem to be an issue with Mercs/OMC, but there have been a number of Suzuki's with busted cav's that were running fins - so take note if you are a 4 stroke Johnson owner - they were built by Suzuki the entire time the Johnson 4 strokes were in production.

As suggested, I found by simply shifting some weight forward you can get all the benefits of a fin.

And think about it - if they were the next best thing don't you think the mfg's would simply build motors with more pronounced cavitation plates?"
 
"hydrofoils,....will not,and,c

"hydrofoils,....will not,and,cannot,increase speed.once on plane....they WILL help,gettig outa the hole...
large hydrofoils,of all kinds of composition,...are used ,very successfully,on shallow running bay boats....
very quick hole shot.."
 
"ihave one on a 14 ft soft bot

"ihave one on a 14 ft soft bottom inflatable with 15hp merc,gets on plane NOW . of course i don't worry about all the technical things stresses ,forces,mpg.i love the darn thing,my boat looks like jeff'sat wot,for the price just go buy one and try it."
 
I have a hydrofoil on my 9.9 j

I have a hydrofoil on my 9.9 johnson pushing a 14ft bass tracker and i love it.Works wonders on the river were i fish all the time.would not run the river with out it.
 
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