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Thread: BBC upper valve train oiling question

  1. #1
    Senior Member DYNO OPERATOR
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    BBC upper valve train oiling question

    I think there is an oiling issue on an BBC engine that was just built. I did not build it, but was asked to help. The oiling to the rockers is very minimal. There is some oil, but not much. It is in a pulling tractor and made 1 pull before it was noticed. I inspected all the pushrods and rockers and there is no damage or unusual wear. Both heads seem to be getting the same amount of oil. You can run the engine at 2000 RPM with the valve covers off and it doesn't throw much oil around at all.

    It has a Dart Big M block, 385 Air Flow Research heads, T&D rockers, Bullet .800"+ cam, Bullet roller lifters (MOREL), Moroso billet aluminum oil pump.

    The block has optional piston oilers. There are no oil restrictors in the block to limit oil to the upper end.

    The T&D rockers don't have a oil hole on top, they oil out the front toward the roller.

    I have adjusted oil pressure from 60# up to 80# and no difference.

    Anyone seen this?

    I have heard of having to cut a vertical relief in the lifters on the outer body to get more oil to the upper end. Anyone know about this or can provide a diagram of this modification?

  2. #2
    Senior Member DYNO OPERATOR
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    BBC

    Thanks for the couple PMs about the Big M block having restrictor plugs behind the front oil galley plugs, instead of the rear like on OEM blocks.

    I contacted the builder of this engine, who does some machine work for me, and he said he did not install any restrictors.

    On the Dart blocks I have built, there are 1/4" pipe threads behind the 3/8" pipe plug threads in the front oil galleys that can be used to put drilled plugs to restrict upper oiling, but Dart does not have those plugs in place, so they would have to be added if desired.

    The piston oilers that were special order for this block, and specified by the owner, are eight 1/6" holes drilled to splash oil at the under side of the piston domes. That is oil volume that reduces the oil avalable to go to the top side?

    I just don't know if the previously mentioned lifter modification could help. Dart tech is the source of this I was told by the owner.

    I did not have this issue on the Dart blocks I dealt with previously.

  3. #3
    Senior Member RACING JUNKIE
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    Mark i wrote about the lifter mod that i do a couple yrs. ago. It was because some of the newer lifters have direct roller lub with a .015/.020 hole out the bottom of the lifter for extra oil on the cam and roller. what i do with the lifters without the direct oilers is i grind a 1/16" flat on the bottom half of the lifter ctr. facing side which does the same thing as the pin hole for oiling the roller. But it in no way puts more oil to the top of the engine, and it pulls the oil out of the oil gallies. What the dart tech was talking about was grinding a 1/16" flat on the top half of the lifter and that would put more of an oil mist on the top of the engine, but still wouldn't put direct oiling on the T&D rollers or the springs.

    JMO

    Zip.

  4. #4
    Senior Member EXPERT BUILDER
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    I have valve covers with oilers built in, with lines running from one valve cover to another and to the side of the block were the cam oil galley is. This helps cool the springs and oil the top of the heads.

  5. #5
    Senior Member MASTER BUILDER
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    Mark,there are two holes in the lifter body just above the cutouts that the oil flows thru.A small grouve from that cutout to one of thoes holes will put more oil to the pushrod,maybe more than you want, but it works.Isky Red Zone lifters come that way.Do a search for Red Zone lifter picture and You might see what it looks like.On the edge orifice lifter the more clearance the lifter has in the bore the more oil the pushrod gets.Bill.

  6. #6
    Senior Member RACING JUNKIE
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    Quote Originally Posted by wmeabates
    Mark,there are two holes in the lifter body just above the cutouts that the oil flows thru.A small grouve from that cutout to one of thoes holes will put more oil to the pushrod,maybe more than you want, but it works.Isky Red Zone lifters come that way.Do a search for Red Zone lifter picture and You might see what it looks like.On the edge orifice lifter the more clearance the lifter has in the bore the more oil the pushrod gets.Bill.
    Bill, that makes sense, i didn't realize that all the Morel's had the secondary hole above the cutout, that will definatly put more oil on top, but i think i would grind a 1/16" flat rather than cut a groove to the upper hole, that way the bigger the flat the oil to the top (controlable)

    JMO

    Zip.


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