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  1. #1
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    mercury 2.5 performance upgrades?

    i have an 03 carbed 200hp. was wondering what stuff i could do to get more performance out of it? its all stock. just looking for some common mods. thanks. this is a cdm style engine.

  2. Member
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    #2
    got plenty super unleaded in your area will be needed for higher compression engine mods reeds might help lil bit
    .................................................. ...the scariest thing in life is the unknown ...................................

  3. Member
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    #3
    Remove the black boxes if it has them, fiberglass CCM reeds, cut heads, cut front half, maybe intake spacer
    90 Shadow 20' Mod V w/ 200 Merc - Total resto and loving it!
    Here's my build from cap-off to boat in the water.
    http://www.bbcboards.net/showthread.php?t=336645

  4. BBC SPONSOR
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    #4
    Quote Originally Posted by rgsauger View Post
    Remove the black boxes if it has them, fiberglass CCM reeds, cut heads, cut front half, maybe intake spacer
    Don't forget the intake stuffers,twice the gain of milling the front half without teardown,and no external dimensions change,so no linkage modifications.Easy to install when installing the reeds.Available for most motors,Chris

  5. Member
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    #5
    No black boxes can be removed on this motor, that was previous years. Believe this is an O ring head so you will need someone who knows how to do that. But in my opinion, seems people would be better off selling the motor they have and buying a used motor with more rated power, if the boat allows it per weight of the new motor or the HP rating.
    Mercury 2002 200hp Carbed Saltwater
    OT566776
    2002 Cape Horn 22' Bay

  6. Member
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    #6
    Trying to get more horsepower out of a motor going on 20 years old.
    You only do that once .....
    1997 Ranger 692VS
    2014 Mercury 175 Pro XS 2B111166

  7. BBC SPONSOR
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    #7
    Quote Originally Posted by Ranger Rod View Post
    Trying to get more horsepower out of a motor going on 20 years old.
    You only do that once .....
    I must have better luck than you....

  8. Member
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    #8
    Quote Originally Posted by ChrisCarsonMarine View Post
    I must have better luck than you....
    Dittos. My 90 V200 is still quite stout. Got your reeds, Chris. Cut heads. No boxes. Pretty stout little motor.

    So your stuffers work? Hmmmmmmm.....

    How about stuffers and spacer? Compound gains or not so much? Have to run with out air box for clearance on stock 200 cowl?
    90 Shadow 20' Mod V w/ 200 Merc - Total resto and loving it!
    Here's my build from cap-off to boat in the water.
    http://www.bbcboards.net/showthread.php?t=336645

  9. Member
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    #9
    Quote Originally Posted by rgsauger View Post
    Dittos. My 90 V200 is still quite stout. Got your reeds, Chris. Cut heads. No boxes. Pretty stout little motor.

    So your stuffers work? Hmmmmmmm.....

    How about stuffers and spacer? Compound gains or not so much? Have to run with out air box for clearance on stock 200 cowl?
    U wont b able to use airbox

  10. BBC SPONSOR
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    #10
    The stuffers work,065 thick for the 5 petal horizontal,equals all you can mill off the crankcase front,a proven mod.For the 96 and up motors with the 4 petal cages the stuffers are twice as thick,.125...if you tried to cut your crankcase that much you would be well into the bleed line valves.Another nice thing is the motor maintains it's outside dimensions,so no linkage shortening is necessary,as well as the obvious no need to tear down the motor and visit someone with a milling machine.
    The spacer will work on a carb motor with airbox removal,and a little trimming in the cowling pans.An efi motor would require re-mounting the ecu in the boat,or a racing cowling,Chris

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    #11
    Don't forget the hood scoop mod. Most other mods give you a lot more bottom end and mid range torque. The hood scoop mod gives more on top end, with no bad affects.

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    #12
    Relieve the exhaust?
    1997 Ranger 692VS
    2014 Mercury 175 Pro XS 2B111166

  13. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #13
    Please take a moment to review the Announcements at the top of the Forum, and update your post with the REQUIRED info (serial number). Thank you!


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
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  14. Member
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    #14
    Quote Originally Posted by ChrisCarsonMarine View Post
    The stuffers work,065 thick for the 5 petal horizontal,equals all you can mill off the crankcase front,a proven mod.For the 96 and up motors with the 4 petal cages the stuffers are twice as thick,.125...if you tried to cut your crankcase that much you would be well into the bleed line valves.Another nice thing is the motor maintains it's outside dimensions,so no linkage shortening is necessary,as well as the obvious no need to tear down the motor and visit someone with a milling machine.
    The spacer will work on a carb motor with airbox removal,and a little trimming in the cowling pans.An efi motor would require re-mounting the ecu in the boat,or a racing cowling,Chris
    Was able to install the spacer on my 94 200 Xri, keeping oil injection intake (had to make a custom linkage), and ecu in place. Little more of a challenge mounting the cowl since there is minimal extra space, but it locks down fine and no rattles or signs of rubbing. This is the older style cowl, not sure if 96 and up would work or not.

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    #15
    Thanks Chris. Much gain with intake and stuffers or are stuffers the biggest bang for buck? WH46 carbs
    90 Shadow 20' Mod V w/ 200 Merc - Total resto and loving it!
    Here's my build from cap-off to boat in the water.
    http://www.bbcboards.net/showthread.php?t=336645