pump question
+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 14 of 17

Thread:
pump question

  1. #1
    The Brown Bomber oldmudwiser's Avatar
    Join Date
    Apr 2010
    Location
    apple valley ca
    Posts
    91

    Default pump question

    12jb-a.. ok im running a little less than 500 hp and it stops at 4100.just wondering i need a diffent impeller?

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    Senior Member jetboatperformance's Avatar
    Join Date
    Dec 2007
    Location
    Atascadero Calif
    Posts
    7,464

    Default

    Sounds like your down on power a bit assuming its an A impeller , I'd be looking at tune up etc , just curious what altitude ? Tom

  4. #3
    Senior Member GT Jets's Avatar
    Join Date
    Jun 2008
    Location
    Morgan Hill
    Posts
    2,234

    Default

    Quote Originally Posted by oldmudwiser View Post
    12jb-a.. ok im running a little less than 500 hp and it stops at 4100.just wondering i need a diffent impeller?


    1. Have you verified the tach.

    2. Like Tom stated, if at altitude you may not be makin' the 500 HP.

    3. Has it ever run a higher RPM?, If so check for the rope around the pump shaft scenario
    GT


    Quote Originally Posted by Quickjet View Post
    Put a 300 on the back of it, Flywheel it and a nosecone. $15,000 later you'll have a 65 mph pile of shit......

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member DuaneHTP's Avatar
    Join Date
    Dec 2007
    Location
    Shell Knob, MO
    Posts
    1,379

    Default

    Is your 500 HP from a guess or is it from a dyno sheet? If from dyno sheet, what rpm did it make the 500 HP at? 4100 on an "A" impeller would be about 250 HP. 4100 on an "AA" impeller would be about 300 HP.

  7. #5
    The Brown Bomber oldmudwiser's Avatar
    Join Date
    Apr 2010
    Location
    apple valley ca
    Posts
    91

    Default

    the less than 500hp is just a gess from the guy who did the machineing.
    im about at 3500 ft. so i gess i my hp is more like 450.

    429 bbf
    60 over
    460 heads
    almost 11 1/2 to 1 com
    big cam
    holley 750 vac secondary..im working on this one trying to get a dubble pumper.

  8. #6
    The Brown Bomber oldmudwiser's Avatar
    Join Date
    Apr 2010
    Location
    apple valley ca
    Posts
    91

    Default

    Quote Originally Posted by GT Jets View Post
    1. Have you verified the tach.

    2. Like Tom stated, if at altitude you may not be makin' the 500 HP.

    3. Has it ever run a higher RPM?, If so check for the rope around the pump shaft scenario

    its been running for a few months and its allways ran 4100. and i did suck the rope up one time but i cut it out.

  9. #7
    Senior Member jetboatperformance's Avatar
    Join Date
    Dec 2007
    Location
    Atascadero Calif
    Posts
    7,464

    Default

    Quote Originally Posted by oldmudwiser View Post
    its been running for a few months and its allways ran 4100. and i did suck the rope up one time but i cut it out.
    The alitude isn't helping and theres a good possibility theres still rope in the exit side (back side of the Impeller Tom

    see what your timing is at and depending on the motor you may be able to run a bit more than a sea level "tune"

  10. #8
    JRPM/e-PerformanceMarine Squirtin Thunder's Avatar
    Join Date
    Dec 2007
    Location
    Bullhead City, AZ
    Posts
    2,034

    Default

    If you have a stock A impeller in that pump with the engine you have and 36* total timing it should turn at least 4600rpms. In most cases I see 4800rpms.
    Jim & Amanda Rich
    CJ 72 & 53c

    JR Performance Motorsports

  11. #9
    Senior Member GT Jets's Avatar
    Join Date
    Jun 2008
    Location
    Morgan Hill
    Posts
    2,234

    Default

    Quote Originally Posted by oldmudwiser View Post
    the less than 500hp is just a gess from the guy who did the machineing.
    im about at 3500 ft. so i gess i my hp is more like 450.

    429 bbf
    60 over
    460 heads
    almost 11 1/2 to 1 com
    Too Big of big cam
    holley 750 vac secondary..im working on this one trying to get a dubble pumper.
    Just sayin' you ran out of torque to accelerate any more.....Just a guess.
    GT


    Quote Originally Posted by Quickjet View Post
    Put a 300 on the back of it, Flywheel it and a nosecone. $15,000 later you'll have a 65 mph pile of shit......

  12. #10
    Senior Member
    Join Date
    Sep 2008
    Location
    OC, CA
    Posts
    273

    Default

    If your going to upgrad to a DP, get at least an 850. Built up 429/460's like a lot of carb.

  13. #11
    Senior Member
    Join Date
    Dec 2007
    Location
    Green Bay Wi,USA
    Posts
    441

    Default

    Talk to Lakes Only, The ford timing chain may have built in retard that was an emissions fix back in the 70's. this drops the power big time. Are you running headers?

  14. #12
    Senior Member
    Join Date
    Apr 2008
    Location
    valley springs, ca
    Posts
    1,244

    Default

    lakes only did some heads for me. way awsome guy and knows his fords. highly recomended

  15. #13
    The Brown Bomber oldmudwiser's Avatar
    Join Date
    Apr 2010
    Location
    apple valley ca
    Posts
    91

    Default

    thank u guys. my mom just pasted on monday so im done with the boat for a while.

  16. #14
    Senior Member
    Join Date
    Feb 2008
    Posts
    546

    Default

    my condolences, sorry for your loss.

+ Reply to Thread
Page 1 of 2 1 2 LastLast

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in


Digg This Thread

Posting Permissions

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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95