Oil pump testing

Discussion in 'Small Block Tech' started by UNDERDOG350, Oct 5, 2019.

  1. Mart

    Mart Gold level member

    Yep, I agree. I've never had to use a steel booster plate, hi- volume kit, or adjustable regulator. Good/proper bearing clearances seem to do the job, along with oil pump gears being set at tight sided tolerances.
  2. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Something else to consider why the low idle OP after exiting the freeway might be that there is a bunch of oil under the valve covers that hasn't drained back into the pan to be recycled yet?

    Could even be a combo of the above AND the oil that IS in the pan is aerated?

    Whatever the deal is the sbb 350 would definitely benefit from an extra capacity oil pan with performance mods.
  3. UNDERDOG350

    UNDERDOG350 350 Buick purestock racer

    Derek, I would agree about the pan.

    This aeration theory should apply whenever maximum oil pressure is reached for a certain amount of time. Say you're on the hwy cruising at 2800 RPM with 55 PSI or running down the track at 5500RPM at 55 PSI. On the exit ramp stop you have low pressure. At the time slip shack you do not. Why is it different? Heat would be a guess.
  4. UNDERDOG350

    UNDERDOG350 350 Buick purestock racer

    Larry gets his wish next weekend. Hot oil testing.
  5. OddfireV6

    OddfireV6 Active Member

    Another thing to watch for related to oil pressure is the new Melling stock lifters flow more oil up through the pushrods than the original Buick lifters did. They are actually Pontiac/Oldsmobile lifters. This includes TA's lifters. I talked to them on the phone about it and their part number matches Melling. As far as we know, no manufacturer is making low-flow lifters like the original Buick ones. That is less oil volume and less oil pressure for the rest of the engine. It's also oil pumped out of the oil pan and up into the top side of the engine where it must drain back down. That is less oil in the pan to keep the pickup covered.

    Many Buicks for decades, even back to the straight-8 days, did not use valve stem oil seals or even umbrella-style oil deflectors on their exhaust valves because they did not flow enough oil up to the rocker arms to need them. Well, the new lifters flood enough oil up there to cause those engines to burn a ton of oil unless the flow is either restricted back down or some kind of oil seal or deflector is installed on the valves. Then you must keep using the higher oil flow, because low oil flow plus stem seals/deflectors would not be enough valve stem lubrication. Galling and seizing valve stems is not something you want to do.

    I take the oil metering disks out of the original Buick lifters and install them into the new lifters. More oil down south where it's needed and higher oil pressure. That is how Buick built them originally.
  6. Mark Demko

    Mark Demko Well-Known Member

  7. Schurkey

    Schurkey Silver Level contributor

    Damn right. Increased oil flow through the lifter never occurred to me.
  8. Mart

    Mart Gold level member

    Just a thought...... Does anyone like Smith Bros, make custom pushrods that could possibly be made with a smaller oil hole on the ends to restrict the flow up top some?

    You would have a B of a time trying to swap the discs out in hyd. roller lifters.
  9. OddfireV6

    OddfireV6 Active Member

    Don't forget about worn lifer bores.
  10. Mark Demko

    Mark Demko Well-Known Member

    From what I've seen on retrofit rollers (link bar) I think they are not serviceableo_O
  11. Mark Demko

    Mark Demko Well-Known Member

    I wonder what decade they (lifter manufacturers) decided to concede and just make a "universal" .842 dia. lifter?
    Late 70's, 80's 90'so_O
  12. UNDERDOG350

    UNDERDOG350 350 Buick purestock racer

    Well the hot testing didn't work out. I could only get the oil up to about 175 degrees. The oil really foams at higher temps and was splashing everywhere. I had the drill rigged to make 20 PSI at 65 degree oil and when the oil got hot and thin the drill RPM went up a little from the lower resistance and it made 24 PSI. It was just like when you take off at idle speed and the pressure jumps up quickly. Very RPM sensitive at low speed.
    The good news is the garage didn't burn to the ground but does stink like burnt oil.
  13. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Thank You for trying Steve.
  14. sean Buick 76

    sean Buick 76 Buick Nut Staff Member

    Synthetic Oil is far less effected by heat.
  15. Mart

    Mart Gold level member

    Sounds like you made a big mess.....:D
  16. Mark Demko

    Mark Demko Well-Known Member

    I believe it DID work out.
    You proved the oil really aerates at higher temps, what kind of oil are yah using?
    johnriv67 likes this.
  17. UNDERDOG350

    UNDERDOG350 350 Buick purestock racer

    The synthetic foamed at room temp. But maybe it would be better with heat. I will stick to conventional.

    That was penzoil 10w30 conventional that I've been using for all the testing. I don't use Penzoil in anything I drive. It was a gift.

    Kind of makes a case for using an oil cooler, better oil pan/windage tray combo and maybe knife edge the crank.

    If I get really bored this winter I may try it again.
    300sbb_overkill and Mark Demko like this.
  18. Mark Demko

    Mark Demko Well-Known Member

    VERY interesting results Steve:cool:
    Interesting about the synthetic foaming at room temp.
    I watched a few vids on You Tube about oils, and it seems foaming is pretty low on the list of their priorities.
    What is causing the foaming? Is it foaming right out of the pump?
    Im not a fan of engine oil coolers unless your towing where the engine is under load. Additional hoses, a cooler, filter adapter, etc, makes me uneasy.
    A deeper pan and windage control I think is the ticket:D
  19. UNDERDOG350

    UNDERDOG350 350 Buick purestock racer

    Not sure why the foam. I do need to make changes to the fixture. The pickup needs to be deeper into the oil and the return may need to be submerged also.
  20. Jim Nichols

    Jim Nichols Well-Known Member

    Steve, I think you are on to something about the return needing submerged. It could be aerating the oil.

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