jetting on Holley?
+ Reply to Thread
Results 1 to 4 of 4

Thread:
jetting on Holley?

  1. #1
    Senior Member rpm0414's Avatar
    Join Date
    Oct 2011
    Posts
    459

    Default jetting on Holley?

    Another motor question guys-- when I rebuilt my carb I noticed front jets were 72's and rear were 84's. Holley lists this as stock. Wow that's quite a rich secondary? Is this normal for jet boat? Once again the boat thing is new to me so just asking.

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    S&S
    S&S is offline
    Steve S&S's Avatar
    Join Date
    May 2011
    Location
    Granite Bay, Ca
    Posts
    179

    Default

    Probably no power valve provision in the secondary side metering block. Power valve ads something like 8-10 jet sizes.

  4. #3
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,529

    Default

    Quote Originally Posted by rpm0414 View Post
    Another motor question guys-- when I rebuilt my carb I noticed front jets were 72's and rear were 84's. Holley lists this as stock. Wow that's quite a rich secondary? Is this normal for jet boat? Once again the boat thing is new to me so just asking.
    S&S is right. You looking at this from the wrong end. Its not that the secondary is rich, its that the primaries are jetted for lean cruize. When the carb is open enough to bring in the secondaries, the PV on the primary side will be open and the jetting will be much more equal.
    I would GUESS that this is a vacuum secondary carb, or an possibly an early double pumper. Most hi perf carbs have a closer pri/sec jetting because the power valve restrictor jet tends to be smaller than street carbs. Realistically, most newer double pumpers and hi po carb PVs add closer to 4-6 jet sizes, were as street carbs can add up to 8 or 10 as S&S posted.
    LINK:GN-RACING.COM

    "there are too many pigs for the teats"
    Abraham Lincoln

  5. #4
    Senior Member rpm0414's Avatar
    Join Date
    Oct 2011
    Posts
    459

    Default

    Got it. Yes vac secondary. Makes sense, I'll keep it like that then. Ran good before new motor build. Rebuilt it and noticed difference. Thanks guys

+ Reply to Thread

Quick Reply Quick Reply

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.

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


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