Weight distribution and Smart Tabs????

[Rick_Criswell]

First Thank you for all of the information available on this site. I have learned a lot in my 6 months lurking and reading here.

Now for some opinions and advice.
Pertinent info.
84 Charger Spirit 1600 Bow Rider
Deep or modified V hull design ? 750 lbs dry weight for hull
Hull 15'7" long 74'wide
84 Mercury InLine 6 90hp
2 6 gallon fuel tanks slide back and drop in just above the bilge pump
6 persons or 900lbs or 1500lbs persons and gear

My delima????? Bought the boat last September
With 4 people in the back of the boat during winter I needed to shift weight forward (Trolling battery, and spare 6 gallon fuel tank, anchor..)
or I would have excessive bow rise on hole shot.Scares the wife pretty badly.

Now that it is summer temps, the wife wants to sit up front with the dogs if it is just us. Or the sister or daughter or daughter in law or her friends or .. you get the picture . She likes to sit in the front.
Now I have too much weight in the front with 2 people in the front .

Here is my thinking from reading this forum.
Shift my trolling motor battery back to the rear . Spare fuel tank back to the rear, can be shifted to either side for ballast. Next install a set of smart tabs to hold the bow down on hole shot for the wife. And to add lift to the stern to help compensate for the added weight in the rear with 4 people in the rear .

 

[studlymandingo]

Re: Weight distribution and Smart Tabs????

Tabs will certainly help. You may have be firm about weight distribution for hole shot though.

What is your WOT RPM? I would think that 90HP would have no trouble handling a boat that is under 16'.​

 

[Rick_Criswell]

Re: Weight distribution and Smart Tabs????

WOT is 4800rpm 42mph trimmed out just before porpoising(?) with 4 people, cooler, and fishing gear.
Prop is a Quicksilver 13.75x19p SS with exaust vent holes. Hole shot is not a problem except for excessive bow rise.
But if I then put two people in the front with the extra battery and gas in the nose I begin to porpoise before I can trim out and get the bow up for smoother planeing.
2 people changeing seats from the very back of the boat to the very front changes the way she handles dramatically.

 

[studlymandingo]

Re: Weight distribution and Smart Tabs????

Sounds like you are over-propped. Your WOT should be considerably higher (5200-5600). You will probably gain some top-end speed as well since your motor isn't spinning up to develop max HP.​

 

[LubeDude]

Re: Weight distribution and Smart Tabs????

It sounds to me like he isn`t able to run it flat out right now because things start to happen first so the prop may be OK. But a 17P might be better. That boat should fly with the right set up. I`d say 50 MPH or better.

That engine is very heavy and I`m not sure where to start with all the imfo you have given us. With you wife always changing her position. Smart tabs will help with your hole shot, but then if your wife moves up front they could actually be detrimental pushing your nose down even more. I`m really not sure you are going to be able to cure all your problems.

Solutions:

Bigger boat:

More HP:

Smaller wife:

Smaller dog:

 

[QC]

Re: Weight distribution and Smart Tabs????

Helm adjustable tabs would allow you to set your weight distribution up for max performance witrh an "average" load, and then you could use the tabs only when necessary to correct for porpoise, people, fuel, stuff, beer and more beer . . .

 

[Rick_Criswell]

Re: Weight distribution and Smart Tabs????

Are you sure on the rpm range. I was trying to keep it in the 4500-5000 range. From my reading I thought the inline 6 stated 4500-5000.