Need help with putting 455 heads on a 430.

Discussion in 'Street/strip 400/430/455' started by Buick Derby Man, Nov 24, 2016.

  1. Buick Derby Man

    Buick Derby Man Buick Derby Man

    Building a 430 from a '69 Wildcat. The car has been in my family its whole life. I was hoping to use the original heads but the machine shop found numerous cracks in both heads. Fortunately, I have many 455 motors and lots of spare heads lying around.

    Today, I went through my head pile and pulled out a set of 1970 heads and a set of 1973 heads. The '73 heads were produced earlier in the run so they only have the single water hole which will match up to the '69 block fine. The '73 heads are ready to go to the machine shop. The '70 heads have several broken exhaust studs and will require at lot more work on my part or a lot more money at the machine shop in order to remove the broken studs.

    Here are my questions.

    1) Is there much power difference between the two sets of heads?
    2) The rockers were oiled differently on the '69 models as compared to the '70 and later models. Is this ok as long as I use push rods with the hole in the center and the later 1970 or later rocker arms?
    3) Is there anything else I am not thinking about?

    Thanks!
     
  2. knucklebusted

    knucklebusted Well-Known Member

    I'm sure others will chime in but this is what I remember. Don't take it as gospel until someone with more knowledge pipes up.

    1) If you cut the 73 heads for the same volume as the 69 heads, it should be red apples to fuji apples close enough. Don't forget that replacement head gaskets are thicker when/if you mill the heads.

    2) I'm not the expert but I think there are very specific things you need to do to convert, possibly changing lifters as well to oil through the push rods in addition to hollow push rods and later rockers. If you do go to later model oiling, you will want to plug the holes in the block deck that fed oil to the heads/rockers to avoid a nagging oil leak problem.

    3) Make sure the replacement 73 heads have any smog holes plugged. You can check by seeing if anything is left uncovered by the 69 intake gasket. It should be pretty obvious if you compare them.
     
  3. Buick Derby Man

    Buick Derby Man Buick Derby Man

    Thanks for the advice. Very good info. The motor already had an Edelbrock intake that I plan to re-use. I believe this will take care of covering all the smog holes.

    I hadn't thought about plugging the oil hole coming out of the block deck. The bottom end of the motor is already re-built and assembled. Yikes.
     
  4. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Lifters are different for through the push rod oiling. Rockers/shafts are different as well. Head cc differ by about 4cc.

    [​IMG]
     
  5. greatscat

    greatscat Well-Known Member

    No problem on plugging the holes, done it before with assembled shortblocks.

    Push a small piece of cloth into the hole so its about 3/4" below surface.
    Turn the block upside down, lay on your back and drill the hole to 3/8"about 1/2'' deep. Remove cloth with tweezers, if you have a pencil magnet run it up and down the hole just to make sure its clean.
    Get a 3/8' freeze plug ,put some lock tite on it and tap it in. Done.
    gary
     
  6. buicksstage1

    buicksstage1 Well-Known Member

    TA 1405 lifters work with both 3/8 and 11/32 push rods by design.
     
  7. hugger

    hugger Well-Known Member

    I've just drove some steel rod down the hole with loctite around it.
     
  8. greatscat

    greatscat Well-Known Member

    What diameter steel rod are you able to use?
    gary
     
  9. hugger

    hugger Well-Known Member

    I think if I remember rite 1/4in was a hammer tight fit, maybe it was 11/32, hell it may have even been the shank part of a bolt I cut down ha, hard to say been years since I've done it
     
  10. greatscat

    greatscat Well-Known Member

    1/4" too small, 3/8" too big. maybe the 11/32 is the trick. I'll need to check I've always used 3/8 freeze plug after drilling.
    gary
     
  11. deluxe68

    deluxe68 Well-Known Member

    I was going to use the freeze plug method when I did mine but I found it easier to use
    a tapered dowel pin from McMaster Carr.
     
  12. Buick Derby Man

    Buick Derby Man Buick Derby Man

    Good advice. I haven't looked at the block yet. Is there just one oil hole on each side of the block?
     
  13. Buick Derby Man

    Buick Derby Man Buick Derby Man

    Thanks for all the replies. I will probably opt to drill it out and put in a freeze plug.
     
  14. hugger

    hugger Well-Known Member

    Just driver front
     
  15. Schurkey

    Schurkey Silver Level contributor

    What engine am I thinking of? Somewhere I heard that another difference between pushrod oiling and block-deck oiling was that the rocker shaft had to be flipped over. Is that the SBB? Or the BBB? Or am I hallucinating?
     
  16. john.schaefer77

    john.schaefer77 Well-Known Member

    I thought 430's and 400's had the hole on both sides and the 455 only on the driver.
     
  17. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Correct, see post #8 in the oiling mod thread by Jim Weise,

    http://www.v8buick.com/showthread.php?214613-400-430-455-Block-ID-Prep-and-Oiling-mods

    From that thread,

    "Background: When first developed, the 400/430 motors oiled the rockers thru two holes in the block, one in each deck surface, to corresponding holes in the heads. When the factory went to pushrod oiling in 1970, they eliminated the hole in the passenger side of the engine, but had to keep the one in the driver side, as this hole, on the other end of it, is the hole that allows oil to feed to the driver main galley, across the front cam bearing. Since drill bits make straight holes, we end up with a pressurized oil hole at the deck, that head gasket has to seal. No real problem with that at 45psi, but when you push the oil pressures up to 75+, it can leak oil out the head gasket."

    [​IMG]
     
  18. deluxe68

    deluxe68 Well-Known Member

    When installing 455 heads on a 430 block I needed to,
    Block the oil feed hole, purchased 455 lifters, push tubes, rockers, shafts and head gasket.
    The heads already had the shafts and rockers, I just wanted the new steel ones.


    From post #8
    http://www.v8buick.com/showthread.php?214613-400-430-455-Block-ID-Prep-and-Oiling-mods



    LH Deck oil hole plug

    Purpose: Plugging an unneeded pressurized oil hole, at the deck surface on a 455, or any BBB that you have converted to thru the pushrod oiling.

    Background: When first developed, the 400/430 motors oiled the rockers thru two holes in the block, one in each deck surface, to corresponding holes in the heads. When the factory went to pushrod oiling in 1970, they eliminated the hole in the passenger side of the engine, but had to keep the one in the driver side, as this hole, on the other end of it, is the hole that allows oil to feed to the driver main galley, across the front cam bearing. Since drill bits make straight holes, we end up with a pressurized oil hole at the deck, that head gasket has to seal. No real problem with that at 45psi, but when you push the oil pressures up to 75+, it can leak oil out the head gasket.

    When to do: All 455 engines, or any BBB that has been converted to thru the pushrod oiling.

    Tools required:


    • 1/8 NPT tap and holder.
    • 3/16 allen wrench


    Supplies required:


    • 1/8 NPT allen head plug.


     
  19. knucklebusted

    knucklebusted Well-Known Member

    I turned down a short piece of aluminum rod stock in my drill press to a taper and hammered it into the block flush with a punch.
    Deck Plug.jpg
     
  20. gymracer01

    gymracer01 Well-Known Member

    Been awhile but I thought there were exhaust crossover and exhaust holes in the heads to the intake issues when switching 73 heads on older engines if you are using the early intake.

    Jim Netherland
     

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