Stabiliser/Hydrofoil for '81 Merc

andrewkafp

Lieutenant Commander
Joined
Mar 15, 2003
Messages
1,668
Re: Stabiliser/Hydrofoil for '81 Merc

How silly of me... :confused: I meant to mention it.<br />It's a 50 HP 4cyl 2 stroke.
 

JasonB

Lieutenant
Joined
Feb 10, 2003
Messages
1,455
Re: Stabiliser/Hydrofoil for '81 Merc

I have a similar product on my 15' Tri-hull w/85hp. I ran a couple times this year without it, then immediately put it back on. It pops up on plane faster, with less bow rise, and holds turns 300% better. Before it would slide the stern out easily. Much better now. That being said, I also tried one on my 19' stern drive V hull. It came back off about as fast as it went on. It hurt more than it helped on that heavy of a boat. Just ordered some Smart Tabs to hopefully fix that boat's bad habits.
 

rdmcphe

Cadet
Joined
Jan 11, 2002
Messages
17
Re: Stabiliser/Hydrofoil for '81 Merc

I have a 1980 Mercury 50hp (4-cyl) on a 15.5 fiberglass boat. I have been tempted to get a set of fins as this boat/motor combination is likely to benefit from a set of hydrofoils. In the past I have had trouble planing with a heavy load.<br /><br />I decided not to get them. Here is why:<br /><br />1. I have read some scary accounts of rolling to the side when turning sharply in displacement mode. This is more likely to happen if the boat is v-bottomed and the motor is trimmed in too far.<br />2. I do not have enough clearance between the hydrofoil fin and my kicker motor. The prop on the kicker will hit the fin if the motors are turned in opposite directions.<br />3. Mercury does not like them. See http://www.mercurymarine.com/general#1029 <br /><br />So how did I solve my planing problem? I reduced 1" of prop pitch and made sure I am propped to the high end of the WOT rpm range (5500 rpm for a Merc 50 4-cyl). I needed a spare prop anyway.<br /><br />This solved the planing problem and top end speed was reduced by less than 1 knot.<br /><br />I hope this helps,<br />Russell
 

CU2NITE

Petty Officer 1st Class
Joined
Jul 9, 2003
Messages
226
Re: Stabiliser/Hydrofoil for '81 Merc

I read the mercury faqs about the stabilizers, and I simpily think this is just to protect them in waranty issues. I have run these stabilizers on a 40 horse jhonson, 50 hp merc, and a 150 merc and I would never go with out one. The extra proformance a boat gets with the stabilizer is unbelievable. Just my experience. Good luck.<br />CU<br /><br />------------------<br />RUNNING THE MOTOR WHILE LISTENING TO THE HORN WILL MAKE YOU MORN!!
 

Jdeagro

iboats.com Partner
Joined
Jul 30, 2003
Messages
1,682
Re: Stabiliser/Hydrofoil for '81 Merc

Unicorn;<br /><br />I am John DeAgro from Nauticus, Inc. and we are the manufacturer of Smart Tabs.<br /><br />Since you are from Australia i thought you might be interested in an article from Powerboat magazine on a similar boat to yours in your own waters.<br /><br />The Jan. 2001 issue of Powerboat magazine in your country wrote an editorial on Smart Tabs (by Jim Harnwell). The boat was a 5 meter aluminium with a 75 hp two stroke Mariner. Here are a few quotes from the editor: "During the four years I've been running my boat, it has displayed no particluar vices when it comes to handling and performance, so i was keen to see what, if any, improvements could be made with the addition of Smart Tabs."<br /><br />"A run out into Jervis Bay with a blustery westerly wind creating substantial chop saw a GPS recorded top speed of 31.5 knots at 5800 RPM, and improvement over non-tab speed of 28 knots at 5600 rpm. I recorded a minimally faster acceleration rate with the Smart Tabs activated. <br /><br />"Driving at speed in a cross wind also resulted in a pleasing discovery. Like most smallish, light boats, my runabout has a tendency to bounce around when driven hard across chop in windy conditions".<br /><br />"Without the tabs the ride was uneven and difficult to control in the chop generated by the 25 knot westerly."<br />"With the tabs the boat handled much better, digging into the water and remaining level and easy to steer".<br /><br />"More interesting was the way the tabs helped push the bow of the boat down when rising up on the plane."<br /><br />I suspect that some or all of the things you would like to fix on your boat are the same as this editors boat. <br /><br />Do a search on this site under hydrofoils and Smart Tabs.
 

andrewkafp

Lieutenant Commander
Joined
Mar 15, 2003
Messages
1,668
Re: Stabiliser/Hydrofoil for '81 Merc

Thanx for the feedback.<br />Will look at these options.<br />Another satisfied Iboats customer. ;)
 
Top