Head porting ???'s
+ Reply to Thread
Page 1 of 3 1 2 3 LastLast
Results 1 to 14 of 36

Thread:
Head porting ???'s

  1. #1
    Senior Member 2savage4you's Avatar
    Join Date
    Dec 2007
    Location
    Bullhead city AZ
    Posts
    1,417

    Default Head porting ???'s

    I got a set of BBC 290's that were originally oval and now are rect port heads......... ( i bought them this way ) Now can i run a oval port intake or does it now have to be rect port ? Or just gasket match the ports on the intake to match..........

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    Manwhore!!!!! Quick99's Avatar
    Join Date
    Aug 2008
    Location
    Fullerton, California, United States
    Posts
    369

    Default

    Sounds like you need a new set of heads. I would stick with a good set of 781,s or 049,s.

  4. #3
    Senior Member 2savage4you's Avatar
    Join Date
    Dec 2007
    Location
    Bullhead city AZ
    Posts
    1,417

    Default

    Quote Originally Posted by Quick99 View Post
    Sounds like you need a new set of heads. I would stick with a good set of 781,s or 049,s.

    traded my 781's in on these heads and paid $800 for the new ones

    Please dont tell me that i need a new set of heads

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    jetboataholic HawaiianJet's Avatar
    Join Date
    Mar 2008
    Location
    Lexington, KY
    Posts
    2,798

    Exclamation

    Quote Originally Posted by 468Bahner View Post
    traded my 781's in on these heads and paid $800 for the new ones

    Please dont tell me that i need a new set of heads
    Damn you change your mind too much!!!

    HJ

    ***FOR SALE*** 1978 19' Full Stringer Hawaiian Molokai Jet Boat w/ Berkeley 12JC-AB and Chevy 440 Tall Deck ***FOR SALE***

    Quote Originally Posted by mako shark mark View Post
    Oh yeah, Forgot to mention that the hull is a special mixture of speedcote, herculiner and rain-x, all blended together- good for another 8 mph top end.

  7. #5
    mo balls than $cents$ IMPATIENT 1's Avatar
    Join Date
    Dec 2007
    Location
    hugo,okla
    Posts
    11,733

    Default

    Quote Originally Posted by 468Bahner View Post
    I got a set of BBC 290's that were originally oval and now are rect port heads......... ( i bought them this way ) Now can i run a oval port intake or does it now have to be rect port ? Or just gasket match the ports on the intake to match..........
    sounds like someone was shooting for more velocity on the runners.

    you can run a oval intake with rect port gaskets, it'll work, won't be right but it'll work and be sealed up.
    got any pics of the intake ports? there's not much meat there to be removing, hope they didn't get em thin.

  8. #6
    Senior Member 2savage4you's Avatar
    Join Date
    Dec 2007
    Location
    Bullhead city AZ
    Posts
    1,417

    Default

    Quote Originally Posted by IMPATIENT 1 View Post
    sounds like someone was shooting for more velocity on the runners.

    you can run a oval intake with rect port gaskets, it'll work, won't be right but it'll work and be sealed up.
    got any pics of the intake ports? there's not much meat there to be removing, hope they didn't get em thin.

    Im supposed to pick em up here shortly if they ever get finished , so no pics as of yet

  9. #7
    Banned
    Join Date
    Jan 2008
    Location
    El Cajon, CA.
    Posts
    3,605

    Default

    Quote Originally Posted by 468Bahner View Post
    ... no pics as of yet
    Aren't there some pics of heads he's done the same thing to over on the SoCal forum?

    I don't know anything about porting, or why 468Bahner changes his mind so much , but the heads that I've seen the guy redo look extremely similar in port size to stock GM rectangle port heads.

  10. #8
    Senior Member H20MOFO's Avatar
    Join Date
    Dec 2007
    Posts
    4,288

    Default

    I'd say you need a vic jr. and an 800 dp holly.lol Sorry couldn't resist.
    Another Hot Boat refugee

  11. #9
    Senior Member Constant840's Avatar
    Join Date
    Dec 2007
    Location
    Yucaipa, Ca
    Posts
    911

    Default

    This is what my set of 290's had done.

    The even side had some detonation and is now pretty torched. Looking for a core...
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	DSC04613.jpg 
Views:	75 
Size:	26.5 KB 
ID:	17320   Click image for larger version. 

Name:	DSC04615.jpg 
Views:	71 
Size:	23.3 KB 
ID:	17321   Click image for larger version. 

Name:	DSC04617.jpg 
Views:	94 
Size:	36.0 KB 
ID:	17322  
    Last edited by Constant840; 08-22-2008 at 02:13 PM.

  12. #10
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

  13. #11
    Senior Member Constant840's Avatar
    Join Date
    Dec 2007
    Location
    Yucaipa, Ca
    Posts
    911

    Default

    Quote Originally Posted by gn7 View Post
    this begs the questionwhy?
    Well these were on the motor that came in the boat.
    My thinking would be that these are really small heads (101cc) and the more air and air velocity you can muster the better.
    The motor ran really well before the detonation issues.

  14. #12
    Senior Member 2savage4you's Avatar
    Join Date
    Dec 2007
    Location
    Bullhead city AZ
    Posts
    1,417

    Default

    As posted above the question is can i use a oval port intake , nothing about changing my mind And i dont change my mind that often

    i have some pics somewhere , i will post em up

  15. #13
    Senior Member 2savage4you's Avatar
    Join Date
    Dec 2007
    Location
    Bullhead city AZ
    Posts
    1,417

    Default

    Best i got for right now Jim/Rod sorry boys you wont be able to see anything Halfway down the page .......

    http://www.socaljetboats.com/index.php?topic=2830.250

  16. #14
    Senior Member
    Join Date
    Feb 2008
    Posts
    457

    Default

    Quote Originally Posted by Constant840 View Post
    This is what my set of 290's had done.

    The even side had some detonation and is now pretty torched. Looking for a core...

    OUCH, did someone use a chisel and a hammer on those bad boys? Or did they break out something else.....


    As for 2Sav

    The oval intake will work just fine, it won't be "optimum" but it will seal and work good. Hope you're just planning to save for a rectangle intake and not thinking of changing those heads

+ Reply to Thread
Page 1 of 3 1 2 3 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

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