BBC Rectangle port tunnel ram on a oval port head ?
+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 14 of 15

Thread:
BBC Rectangle port tunnel ram on a oval port head ?

  1. #1
    Junior Member zonked's Avatar
    Join Date
    Feb 2012
    Posts
    15

    Default BBC Rectangle port tunnel ram on a oval port head ?

    Bought the wrong port tunnel ram and was just told I can run a rectangle port intake on an oval port head doesnt make sense to me. Anyone have any experience with this ?

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    Senior Member EVILFORCE's Avatar
    Join Date
    Oct 2009
    Posts
    5,180

    Default

    Quote Originally Posted by zonked View Post
    Bought the wrong port tunnel ram and was just told I can run a rectangle port intake on an oval port head doesnt make sense to me. Anyone have any experience with this ?
    Ask the guys who deal with Dyno's a lot. That combo usually makes more power then the oval port manifold does. I am sure Bob or Steel will say something.
    No Fool Like A Old Fool is there?

  4. #3
    Senior Member Mojave85's Avatar
    Join Date
    Feb 2008
    Location
    Boise, Idaho
    Posts
    628

    Default

    PM sent

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member 2002CP19's Avatar
    Join Date
    Jun 2008
    Location
    Lake Arrowhead/Lost Lake
    Posts
    692

    Default

    Velocity!
    Quote Originally Posted by schick View Post
    Hold it firmly on the ground, a few pelvic thrusts should do the trick. If not repeat till satisfied!

  7. #5
    83 Crusader - 468 BBC SNiC's Avatar
    Join Date
    Apr 2011
    Location
    Sweet Home Alabama
    Posts
    2,524

    Default

    Quote Originally Posted by zonked View Post
    Bought the wrong port tunnel ram and was just told I can run a rectangle port intake on an oval port head doesnt make sense to me. Anyone have any experience with this ?
    Please post your findings...I am interested and curious as well



  8. #6
    Member
    Join Date
    Jan 2012
    Posts
    30

    Default sqaire port tunnel ram

    we have done it in the past had good results it was allways on a mild mannered set up . Just be sure to use square port gaskets

  9. #7
    Senior Member ICECREAMAN's Avatar
    Join Date
    May 2009
    Posts
    2,426

    Default

    It will definitely work. I can't see it being the most efficient though, especially on the top end. I ran this combo years ago when I needed a motor to just get the boat wet with so I threw my T Ram on an old wore out Suburban 454 just to finish out the year. It actually didn't run that bad. Just remember to use the intake gaskets that match your intake or you'll have a massive vacuum leak.

  10. #8
    Senior Member Need4Speed77's Avatar
    Join Date
    Jun 2008
    Location
    Q.C./Big River
    Posts
    1,885

    Default

    It will work just fine. I ran a rect port intake on oval port heads for three years. Would I do it on the motor I have now? No, but for a 450-500 hp deal used to cruise on the water it wont make a difference.

  11. #9
    Senior Member jimclauss's Avatar
    Join Date
    Jan 2011
    Location
    Mickleton, New Jersey
    Posts
    1,622

    Default

    Quote Originally Posted by zonked View Post
    Bought the wrong port tunnel ram and was just told I can run a rectangle port intake on an oval port head doesnt make sense to me. Anyone have any experience with this ?
    yes , it works

  12. #10
    Senior Member ol guy's Avatar
    Join Date
    Mar 2008
    Location
    Lake Elsinore Ca
    Posts
    3,818

    Default

    Yea it works. I have a rec tunnel on a pair of ovals and it works real well on my set-up although my heads have been worked a bit on the intake side. Lots of guys have done it and most wouldn't want to admit but let er rip. I have found that it will acctually wakes up the bottom end a pinch, kinda like a velocity thing. Just use the right gaskets!!! Mark

  13. #11
    Senior Member rpm0414's Avatar
    Join Date
    Oct 2011
    Posts
    466

    Default

    Did it once on my drag car. Worked ok. Slowed car meaning less power but it ran

  14. #12
    Junior Member
    Join Date
    Mar 2017
    Posts
    1

    Default Single Carb Tunnel Ram Question

    Has anyone had issues with running a single carb tunnel ram- issues being the fuel mixture is not consistent through out?? I'm looking to run this set up, but have a few people tell me not to because of it leans out the front and back cylinders? Any constructive thoughts/info on this would be greatly appreciated!

  15. #13
    Senior Member ol guy's Avatar
    Join Date
    Mar 2008
    Location
    Lake Elsinore Ca
    Posts
    3,818

    Default

    Quote Originally Posted by Scottlev466 View Post
    Has anyone had issues with running a single carb tunnel ram- issues being the fuel mixture is not consistent through out?? I'm looking to run this set up, but have a few people tell me not to because of it leans out the front and back cylinders? Any constructive thoughts/info on this would be greatly appreciated!
    Alot of factors come to play on this question? Engine size,cam specs and intended carb. Not to mention boat and what you are trying to get out of it. Of Course everybody wants the most bang for the buck but I have done it and made it work. The biggest factor is a LARGE plenum manifold with a single shot carb?. With that being said the squirters and jets need to be stepped up to kill the initial hit from the peddle. As most people have learned with a single top tunnel is that they have a large hesitation on the hit simply because of the plenum which is mostly air and a touch of fuel will toss a big bog on off throttle response. So to cure that issue what would you do. M

  16. #14
    Senior Member Spike Morelli's Avatar
    Join Date
    Jan 2012
    Location
    San Fernando Valley
    Posts
    1,402

    Default

    Since this is a jet boat thread, lets state the bottom line here first. IF you are running a stock pump, you may be limited in rpm that you will realisticly see, due to a stock pump's very nature, around 5500-5600 is my recollection. On our dyno at work, we've found that the oval ports well out pull the rectangular ports up to around that same 5500, where the rectangular ports start to show gains at the higher rpms. I've never purposely run a mis-matched intake/head combo to know , but indications are that if you're running a hot lake or river boat, and not an all-out racing rig turning 7000 rpm with a loosened up pump, shoe, grate, nozzle, etc, the Oval port big Chevy heads are the more efficient flowing , and the aftermarket ovals even more so. Run a matched oval intake to keep velocity high. ( Remember, you're trying to "ram" the air/fuel charge in ). Many builders have even run a slightly larger head port opening as opposed to the manifold's, to create a manifold "lip", to minimize reversion. Running the biggest and baddest components just to have bragging rights often results in an engine that isn't running well. My engine building motto.....Give each particular engine what it tells you it wants, not what you want to give it.

+ 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