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CNC 07-23-2009 08:21 AM

King Demon Jetting
 
1997 31 Awesome, #5's w/Bam's spinning 17.5 x 31's

572, AFR Heads, Dry Stellings, mystery Crane Hyd cam, 32 deg timing, MSD, Blower motors w/blower removed and King Demon box carbs installed

Barry Grant King Demon 1090 straight discharge, 6.5 power valve 94 mains all around.....

I know what I should do.... send to Nickerson.....BUT I just want to get by for the summer , only about 6wks
left for us Mi people. Then I plan I putting my proven Procharger setup on this winter. I bought the boat this way and have yet to get on plane... acts lean... runs rich fouls plugs, won't spin past 2000rpm trying to get on plane.

Just looking for baseline...

My eyes are blood red from reading all night.....Ok all that said....

Should I be running power valves? Brass plug???

Jetting recommendations? run square???

Any other ideas?

Jeff P31 07-23-2009 10:21 AM

If they are the same props you ran with the blowers they are way to big . the motor is not making the power it takes to spin them with out the blowers . just my .02

CNC 07-23-2009 10:46 AM


Originally Posted by Jeff P31 (Post 2916417)
If they are the same props you ran with the blowers they are way to big . the motor is not making the power it takes to spin them with out the blowers . just my .02

Nope they are smaller, w/blowers they spun 34's. Supposedly they (seller) ran 110 w/this setup...... not working for me.

Ran-Dom 32 07-23-2009 11:02 AM


Originally Posted by CNC (Post 2916445)
Nope they are smaller, w/blowers they spun 34's. Supposedly they (seller) ran 110 w/this setup...... not working for me.

That's what I'm wondering, did they actually run it that way, or was that an estimate what it might run? I know it takes close to 700hp to run 110 in that hull ,

tssteph 07-23-2009 12:12 PM

Depends on the gear ratio, do you know what it is? My guess is there is just not enough low end power. Air tubes on the drives may help but are not desirable.

Do the props blow out when coming on plain or does the motors just bog down?

Borrow some smaller props.

Are both motors doing exactly the same thing?

IMO 94s all the way around are to big, but it should still get on plain.

IMO yes on the power valves. If you do not run them the jetting needs to be increased. No real reason in your case not to run them.

I would like to see pics of the stellings in the boat.

Also where is the prop shaft realative to the bottom of the hull? May not be relative to the problem but I am wondering.

CNC 07-23-2009 01:44 PM


Originally Posted by Ran-Dom 32 (Post 2916463)
That's what I'm wondering, did they actually run it that way, or was that an estimate what it might run? I know it takes close to 700hp to run 110 in that hull ,

Yes, they did recall GPS 110 ..... w/blowers 135

Ran-Dom 32 07-23-2009 01:48 PM

another 500 rpm & its should roll over & plane, even overproped it should still plane, are the props staying hooked up?

tssteph 07-23-2009 01:53 PM

You are right 2500 rpm should be close to rolling over. Once on plane I can cruise at 2000 rpm if I need to.

Based on his description it sounds like they are hooked up and the motors won't go over 2k rpm.

5s would be high and I would think blow out would be more likely.

CNC 07-23-2009 01:56 PM


Originally Posted by tssteph (Post 2916527)
Depends on the gear ratio, do you know what it is? My guess is there is just not enough low end power. Air tubes on the drives may help but are not desirable.

Do the props blow out when coming on plain or does the motors just bog down? motors just bogg... it's a carb issue I thought possibly to big??

Borrow some smaller props.

Are both motors doing exactly the same thing? YES

IMO 94s all the way around are to big, but it should still get on plain. from all my reading when running power valves I should be several sizes down on primaries. also I need to do a vacuum reading to figure out correct P/V's


IMO yes on the power valves. If you do not run them the jetting needs to be increased. No real reason in your case not to run them.

I would like to see pics of the stellings in the boat. I would but membership has expired

Also where is the prop shaft relative to the bottom of the hull? May not be relative to the problem but I am wondering.

I will have to measure

tssteph 07-23-2009 03:52 PM

If you ease into the throttle and get it rolling does it still just bogg? I wonder if trimming it up a little might help get the rpms up? Is the boat real nose high and just plowing? Mine does not go nose high and plw at all.

http://www.youtube.com/watch?v=Vw5Zt...&feature=email


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