Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Oval port headers on Rect. port heads?

Discussion in 'The Garage' started by pismorat, Jun 15, 2010.

  1. pismorat

    pismorat 1/2 ton status

    Joined:
    Oct 29, 2002
    Posts:
    535
    Likes Received:
    0
    Location:
    California
    I am putting my 383 full roller stroker in my wife's '69 C10. It has GM Perf. heads with angled plugs and rectangular ports. I ordered a set of Hedman Hedders to clear the angled plugs, but they ended up being oval port...am I going to have a problem if I try to run these?
     
  2. pismorat

    pismorat 1/2 ton status

    Joined:
    Oct 29, 2002
    Posts:
    535
    Likes Received:
    0
    Location:
    California
    Since no one replied yet, I assume it is a bad combination...
     
  3. folkenheath

    folkenheath Worthless Trash Premium Member GMOTM Winner

    Joined:
    Nov 12, 2004
    Posts:
    4,144
    Likes Received:
    54
    Location:
    Wisconsin
    Did someone severely port on those heads? As far as I know there is no such thing as a rectangular exhaust port. There are D-ports. And all small block Chevy's are pretty much rectangular port intake ports, so no one ever uses that term on the small block. But either way, as long as you have enough material to pinch the header gasket and not leak they should be fine. If they are D-ports, usually the header will just be a little too large at the bottom, but still seal against the flat gasket surface underneath. Unless they are a large race D-port or something.
     
  4. Stomis

    Stomis Professional Amateur Premium Member

    Joined:
    Nov 20, 2007
    Posts:
    9,865
    Likes Received:
    106
    Location:
    Roseland VA/PtPleasant NJ
    Yeah in fact oval headers on a D port head is ideal. Creates whats known as a reversion dam which aids in exhaust scavenging with a free flowing exhaust. Basically it doesnt let the exhaust gasses cycle back into the head but instead aids in drawing more gasses out accelerating exhaust flow.
     
  5. pismorat

    pismorat 1/2 ton status

    Joined:
    Oct 29, 2002
    Posts:
    535
    Likes Received:
    0
    Location:
    California
    Cool, so should I just get a good set of gaskets(probably metal) that fit the d-port so they will last and not impede the air path? Or do I get a set that matches the oval port?
     
  6. Stomis

    Stomis Professional Amateur Premium Member

    Joined:
    Nov 20, 2007
    Posts:
    9,865
    Likes Received:
    106
    Location:
    Roseland VA/PtPleasant NJ

    Get a set to match the ovals.
     
  7. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

    Joined:
    Dec 14, 2001
    Posts:
    22,006
    Likes Received:
    39
    Location:
    Pleasanton, CA.
    Almost all SBC exhaust ports are square with the exception of some Corvette heads that had a D shaped exhaust port.

    I have found that the Fel-Pro 1444 gaskets work best on most headers.
     

Share This Page