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97 Nitro 912 Savage  Q: There is considerable bow lift under acceleration and at speeds under 30 mph.
96 200 Merc ProMax Would trim tabs be a good solution to this problem? What type of jackplate should
  I purchase for improved holeshot and top end?  Is a 6" plate going to be sufficient
23" Trophy of should I be looking at 10 inchers?  How many mph should I expect to gain with
70 mph @ 6000 addition of the jackplate and/or a prop change?  The prop I have came with the 
  boat when I bought it used, it is pretty dinged up; is reconditioning the way to go 
  or should I buy a new Trophy or Tempest with more or less pitch for top speed as
  well as improved hole shots?  The water pressure is unknown because the gauge 
  needs to be replaced.  Thanks for your time.........
      A: I'd say a 8" plate is the way to go....the 200 ProMax needs to have a top rpm
  of 6500....adding the plate and a non-dinged 23 Tempest will probably get you on
  up to 6300......that will be close enough.
  You're going to have to have a psi gauge if you add the plate...and a 21 Tempest
  may be necessary to get the engine on up in rpm....as to what gains to be had.....
  I don't know exactly....probably 2 more mph if you are pretty efficient now...if you're
  not very efficient now then 3-4 mph could be possible.
96 Nitro 896  Q: I'm considering an 8" jackplate but have been told that since there is so much
97 150 Merc EFI setback already built into the hull it would be a waste of time and money.
  What's your opinion?  I have tried a couple of different props, i.e., a 25 Trophy
23" Trophy and a 25 Laser II.  Both props run about the same as the 23 with maybe a slight
1.5" off transom edge going to the 25 Trophy which pulls 62.5 on my GPS.  The strange thing is 
62 mph @ 5850 that there is no noticeable difference in holeshot between the three.  This makes no
24# psi sens because the dry hull weight of an 896 is 1715#. The only difference I can tell
  is that with the 25's I can only turn a bit less than 5300 on the top end.
  I don't realy know if there's anything to be gained on the top end cause I run about
  as good as some of the smaller, lighter boats with the same power, but I have a 
  midrange porpoising problem with almost any positive trim.  When in rough water
  I also have problems keeping the hull in the water even with it tucked all the way
  under.  I'm not too sure about propshaft height, but with it trimmed up and aired
  out I lose water pressure down to 10-12 in fairly sharp turns. Thanks for the advice.
     A: I think 8" is too much setback....I'd go 6" max.....and no matter what amount
  of factory hull setback there is, a plate will help.
  If you add the plate everything is going to change....so we won't get into props at 
  this point.....besides, you've pretty much done your testing well up to now and 
found a good compromise.  The plate could cure your porpoise problem....it could
  enhance it also.....my bet is that it will help it.
  Your h20 is fine.........
01 Nitro NX882 SC  Q: Would like better hole shot and want a spare prop anyway.  G&K propellers
01 150 Merc XR6 recommends the 23" High Five.  I was leaning towards the Trophy Plus.  What are
  your recommendations?  I recently installed the CMC Power Lift and really haven't

23 Tempest

had time to fine tune it, so really not sure of the best settings.
6" CMC hydraulic     A: I wouldn't have a HighFive on a tuna boat!.....if you pulled skiers or carried a 
3" below the pad camping load I'd recommend the Vengeance by Merc....holeshot and decent speed...
62 mph @ 5500 Your numbers look pretty good with the setup you have....I'd look for a Trophy and 
12-14# psi run from the H5....you'll lose 4+ mph in a hurry.
   
95 Nitro 2000 DC  Q: Just wanted to know how to get more top end speed.  It is slow getting on plane.
92 200 Merc EFI Just seems like boat should be faster and do you have any idea how heavy this boat
  is, and how much faster would a 225 ProMax be.  Thanks.......
25" Tempest  A: The boat is heavy.....not exact, I know, but a ProMax would NOT function on it
6" jackplate very well.....you'd have to drop to a 19" prop to get 6500 rpm from the PM....that's
2.5" below the pad where it makes power.
63 mph @ 5300 rpm You need rpms.....about 600 of them......and a Trophy to get the boat out of the 
15# psi water some more.  At 5300 you're making about 170 hp instead of the 200 you 
  have on tap.....get a 23" Trophy for starters.....get the r's up and let's see what that
  does.
95 Nitro 180 TF  Q: I just purchased a jackplate.  I was running @ 5200 rpm and 60 mph gps before
95 150 Merc XR6 I installed the jackplate.  I tested it today and could not get the rpm above 5300.
  I did not have my gps with me today to get a speed measure.  Everyone tells me that
23" Tempest the engine should be running around 5600 rpms.  Any suggestions?
6" jackplate     A: Water pressure is getting dangerously low.....5500 is where the XR is 
5300 rpm recommended to operate....but you should have picked up more than 100 r's when
8# psi all is said and done....I'd recommend going up if the h20 wasn't so low.....if your psi
  gauge is hooked into the pee line it will read low....if in the top of the block for an 
  accurate reading then look out....you may be due for an impeller also.
97 Nitro 800 LXS  Q: Just wondering if I can get more top end out of my set up?  I hear the Opti
99 150 Merc Opti water pressure should run around 8-9 psi. Is my motor possibly too low?  Can I 
  raise my motor to achieve a better top end or is that about it for this setup?
23" Tempest The motor height is the same as the dealer set it 3 years ago when the boat was
8" jackplate purchased.  Thanks for any help!
62.3 mph @ 5353     A: 12# psi is the minimum for the 2.5 liter Mercs....10 maybe....but check it in 
14-15# psi the turns....not down the straights. 
  I think you need to start raising the motor some. Get the prop you have to 5500 r's
  and 65 mph and you'll be doing about all there is to get.
98 Nitro 912  Q: Ran 67-68 with 2 people, tourney load, water in the livewells and 1/2 tank of 
98 225 Merc Opti gas.  Ran 5400 rpm. Another question also, I have not been able to get an answer
  to.  I have been getting a warning light (bottom light on gauge), and buzzer going off.

25" Tempest

It seems to only happen when I have idled for long periods.  It will go off sometimes

8" jackplate

while I am still at idle and other times just after I get up on plane at low to med 

70 mph @ 5400

speeds.

20# psi

   A: Speed and rpms look about right for a load.  As for the warning buzzer...don't
  fool around....take it to your Merc tech....Opti's can go quick when the slightest
  problems arise.
98 Nitro Savage DC  Q: The dealer set up the jackplate and I am not sure about the settings, what is
98 150 Merc EFI ideal for all around performance.  I do not have any information from the 
  manufacturer (T&H Marine), detailing how to set this thing up for my application.

23" Tempest

What do you suggest?

6" jackplate

    A: Ideal is what feels good to you...the numbers you gave look very good. If it 

62 mph @ 5800

were mine I'd have pretty much the same prop you have.  I might try to lower the 
  rpms a tad but since they don't make a 24" Tempest I'd stay where I was.
01 Nitro 911 CDC  Q: Todd, I am in the process of breaking in this boat and do not have WOT info 
01 250 Merc XB as of yet.  My questions are: This will be a team tournament boat with full gear for
  both anglers.  Do you think the 25" Tempest Plus is the right prop and what engine

25" Tempest Plus

height do you recommend?  Also, what type of speed can I expect with the 250XB?

10" jackplate

    A: This is a shot in the dark...but, yes, I think the 25" Tempest is a good choice...
  at least till you get broke in and see what numbers you get. This is a big boat....I'd
  guess loaded you'll be looking at 74-76....total guess tho......
98 Nitro 896 Savage  Q: Just installed the jackplate.  Want to know start off point of where to set
98 200 Merc EFI jackplate and what prop should be used.  Thinking about getting a tuned prop for 
  my boat.

25" Tempest

    A: I'd start by setting the center line of propshaft 3" under the pad of the boat.....

7" jackplate

you'll probably work up a tad from there.   Before getting a tune job done, make

68 mph @ 5800/6000

sure you have your setup complete as possible.......
   
99 Nitro 700 LX  Q: Todd, what is your thought on the speed of this boat?  I hear others are getting
99 115 Merc as much as 56 mph out of this boat with the 115 and am not sure if propping up
  would help that much or not, I know the rpms I'm turning is too high and need to do

23" Trophy

something but I think maybe the motor is too high as when I hit wot I can hear the

3" jackplate

prop surfacing.  What are your thoughts?

51 mph @ 5600

 A: If you are surfacing the prop...lowering will drop the r's and increase the speed....

14-15# psi

the h20 psi doesn't look like you're too high....but it's hard to say over the computer.
  The main thing is that until you put a jackplate on it you will never be able to tweak
  it to the max....plus the cleaner water a plate would put you in will let you spin on up
  without surface venting.
95 Nitro 190 DC  Q: Todd, how many rpms should a 150 Mariner turn?  I had the nicks taken out of
95 150 Mariner EFI my prop and when I got it back my motor was turning 6000 rpms at wot, normally
  turned around 5600 at wot and speed was 56-58 which is slow I think. They told me

24" Trophy

that they put a cup in the prop for an I/O motor and not an outboard.  I had to lower

5 1/2" off transom

my motor 2 inches to get the rpms down to close to where they were before.  I have

58 mph @ 6000

a 24" 3 blade Laser prop to try.  What do you think of that, and what speed and

12-14# psi

rpms should my boat set up be?
   A: I'd turn the 150 no further than 5800.  The 24" is history....and I'd be looking for
  a new prop shop also.  It will never be the same.  The Laser II is the biggest turd of
  a prop on heavier boats ever made.....the Shooter by OMC is a close second.
  It it were me, I'd have a 23" Tempest on it....you should be at 56-5800 rpms at an
  honest 60 mph.....maybe a tad more.