changing from an "B" to "A" impeller
+ Reply to Thread
Results 1 to 9 of 9

Thread:
changing from an "B" to "A" impeller

  1. #1
    Senior Member crf311's Avatar
    Join Date
    Mar 2008
    Location
    Meraux, LA
    Posts
    357

    Default changing from an "B" to "A" impeller

    I know this has been answered before, but what can I expect to gain or lose by changing from a "B" impeller to a "A" impeller.
    Do I gain holeshot with an a and lose top end mph?
    I know alot of factors need to be figured in.

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    P/E #426
    Join Date
    Jun 2008
    Location
    Chicago
    Posts
    372

    Default

    Quote Originally Posted by crf311 View Post
    I know this has been answered before, but what can I expect to gain or lose by changing from a "B" impeller to a "A" impeller.
    Do I gain holeshot with an a and lose top end mph?
    I know alot of factors need to be figured in.
    Your going to be moving more water @ a given RPM. The only way to really know is on the clocks. What are you spinning the B currently, and at what rpm. I need details on the motor and cam. Where do you make the power power / tq?
    P/E #426

  4. #3
    Boat 502 76Miller's Avatar
    Join Date
    Jan 2008
    Location
    Huntington Beach, Ca
    Posts
    1,298

    Default

    What will determine your gains is, how the impellor is "detailed". If you have a nice detailed 'b' vs. a stock 'a', the detailed 'b' will be the best of both worlds over the 'a', and vice versa.

    If your changing out a stock 'b' to a stock 'a' your gains will be: better holeshot, low rpm's w/ a nice cruising speed, and gas tanks that don't empty as fast. The only real loss would be less rpm at wide open throttle that would give you less mph. The real question is, what do you mainly use this boat for ? Skiing or hotrodding ? Also, at what rpm does your motor make peak power ?

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member crf311's Avatar
    Join Date
    Mar 2008
    Location
    Meraux, LA
    Posts
    357

    Default

    Thanks for the reply's. I'm running a jacuzzi pump with a alum B in it right now. In the spam section someone is selling a SS A for a jacuzzi. I know my pump right now needs a rebuild so I was thinking of going with the A. I'm looking to cut down my RPM. Haven't used the boat a lot in the past few years do to Katrina, But now all that shits behind and I'm looking to do some boating this summer.
    My dyno on the motor was max TQ of 560lbs @ 4k to 4.5K, max HP 575 @6K.
    HP crosses TQ 5250RPM at 550TQ and HP.
    Motor has a solid flat tappet with 4/7 swap, Roller rockers, Demon 850 DP carb. OTT headers. I have a place diverter also.
    Thanks

  7. #5
    Boat 502 76Miller's Avatar
    Join Date
    Jan 2008
    Location
    Huntington Beach, Ca
    Posts
    1,298

    Default

    With the power your running a s/s impellor is not really needed, although always a nice upgrade. What rpm were you spinning before ? If anything i would cut down the 'A' to an 'AB', if I bought it. If it was mine i would just put a nice detail on the aluminum 'B' that i already own and call it a day.

  8. #6
    Senior Member crf311's Avatar
    Join Date
    Mar 2008
    Location
    Meraux, LA
    Posts
    357

    Default

    Thanks, I was really looking to go with the SS because of the salt in the water down here. I don't run in fresh water to much, mostly brakish/salt water. Thanks again.

  9. #7
    Senior Member hotbo's Avatar
    Join Date
    Feb 2008
    Location
    lake Ouachita AR
    Posts
    4,677

    Default

    imo the b-cut will put your motor where it needs to be to be efficient.with your set-up.detail the b or buy the ss and cut to a b-cut.

  10. #8
    E-7 Sheepdog (ret) SmokinLowriderSS's Avatar
    Join Date
    Dec 2007
    Location
    Newton Ks.
    Posts
    6,834

    Default

    I'm going to be the one to tell you that you are BORDERLINE on overpowering that Aluminum impeller, look it over VERY CLOSELY for cracking. Aluminum stress-fatigues, steel does not (not hardly like Al. does).

    The rest has been pretty well covered, it's not a huge difference, but it is a difference.

    Also, everyone's Tq curve crosses the HP curve @ 5250RPM, by the way.
    Torque is a measured force, HP is a mathematical calculation of torque over time.
    "As democracy is perfected, the office of president represents, more and more closely, the inner soul of the people. On some great and glorious day the plain folks of the land will reach their heart's desire at last and the White House will be adorned by a downright moron."
    H.L. Mencken

    OBAMA: Some people deserve this.
    The rest of us are being dragged along kicking and screaming.

  11. #9

    Join Date
    Jun 2008
    Posts
    101

    Default

    Are you sure the ss impeller will fit the pump you are using?
    Standard 12YJ came with ss, 12WJ came with aluminum and they are not interchangeable.


    Just checked spam, ss for a 12WJ will fit,
    Smaller impeller = better hole shot unless your trying to move a heavy boat.
    Last edited by John Mills; 01-09-2009 at 07:01 PM. Reason: update

+ Reply to Thread

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


Tags for this Thread

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