Results 1 to 6 of 6
  1. #1

    Join Date
    Aug 2007
    Location
    Long Island NY
    Posts
    48

    '99 XPL 951 Head Mod.

    Can someone tell me what is normally done to a stock head to raise the compression and still run pump gas? A basic mill figure off the head, .020?
    Do the shops normally glass bead the combustion chamber? Local shop who does machine work on racing outboards says he can do what ever I want. Any suggestions without reinventing the wheel?
    '99XPL 951. 1st oversize pistons, new rav valves, stage 1 carb mods, exhaust water kit, silencer removed, rear exhaust.


  2. #2
    Banned User
    Join Date
    Dec 2006
    Location
    Crest Hill, IL
    Posts
    9,512
    +1
    215
    Quote Originally Posted by jetcar123 View Post
    Can someone tell me what is normally done to a stock head to raise the compression and still run pump gas? A basic mill figure off the head, .020?
    Do the shops normally glass bead the combustion chamber? Local shop who does machine work on racing outboards says he can do what ever I want. Any suggestions without reinventing the wheel?
    '99XPL 951. 1st oversize pistons, new rav valves, stage 1 carb mods, exhaust water kit, silencer removed, rear exhaust.


    Usually it is shaved to the requirements the shop knows is safe, roughly up to 15% more than normal (like 130# to 150#)...and still run on pump gas. Some machine shops also will reshape the combustion chamber. Never sean them glass bead the chamber...

  3. #3
    David 1 FAST VE's Avatar
    Join Date
    Jun 2005
    Location
    Southaven, MS
    Posts
    1,958
    +1
    1
    Yea just milling a head is sort of a hack way to do the job.
    Not that it won't work but the squish has to be addressed to do the job correctly.

    David

  4. #4
    96XPSS's Avatar
    Join Date
    Feb 2006
    Location
    Warner Robins, GA Home of the 2007 All-Star Little League World Champions!
    Posts
    4,361
    Never glass bead a combustion chamber. Rough spots absorb heat, and lead to deto, and big melted holes.

    Get the squish band cut too, a must.

    Buy a Miller head is my recommendation.

  5. #5

    Join Date
    Aug 2007
    Location
    Long Island NY
    Posts
    48

    951 head mill

    Thanks for the info, I bought a Miller head. That took out all the guess work.

  6. #6
    96XPSS's Avatar
    Join Date
    Feb 2006
    Location
    Warner Robins, GA Home of the 2007 All-Star Little League World Champions!
    Posts
    4,361
    Quote Originally Posted by jetcar123 View Post
    Thanks for the info, I bought a Miller head. That took out all the guess work.
    You'll be very pleased with the head...Mel makes great stuff. There is a lotta shita in the PWC world...Mel delivers.

    Good luck and enjoy!

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. 99 xpl 951 exhaust water injection mods
    By michxpl in forum 2-Stroke Performance
    Replies: 3
    Last Post: 02-17-2015, 10:49 AM
  2. 99 XPl 951 Fuse issue
    By southernflip in forum 2-Stroke Performance
    Replies: 3
    Last Post: 07-21-2013, 10:30 AM
  3. 99 XPL 951 top end rebuild
    By JohnMstrks in forum 2-Stroke Performance
    Replies: 5
    Last Post: 09-02-2011, 12:30 PM
  4. FS 99 XPL 951 parting out
    By WFO in forum Sea Doo Classifieds
    Replies: 13
    Last Post: 07-08-2010, 09:51 PM
  5. 99 xpl wire head spin!!
    By clownhands in forum 2-Stroke Performance
    Replies: 8
    Last Post: 02-09-2010, 11:23 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •