Quote:
Originally Posted by Lynn Eades
When I said "full flow" I was talking about the std. system (95%)
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Sorry Lynn, I thought you meant "true" full flow.
Quote:
Originally Posted by Lynn Eades
I guess I just haven't established the reason(s) why Ford made that adapter with clearance around it, rather than having a completely sealed system of one definative flow path...... Or am I not understanding something?
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Yes Lynn, it appears you and Malcolm have misunderstood the screw-in adapter. It's not designed to provide bypass flow to the motor. That function is performed by the external bypass valve. As Malcolm says: "The tubing extension on it is 3/8" OD, which is a fairly snug fit in the vertical passage coming up from the pump." In other words, just enough clearance to avoid binding when screwing in and out. Any leakage past the sides would be miniscule, as the pressure differential between the two passages is perhaps 5 psi at most. I believe the bypass valve is set at 10 psi (?) to ensure adequate flow to the motor when cold. Of course, it relies on the cooler being full, as you guys mention.
Quote:
Originally Posted by Lynn Eades
the hole in the adapter would be a restriction (little over 1/4") and much smaller than the main galleries in the block.
The Aussies plugged the cross drilling in the Aussie carriers (in the parts book) but used std fittings without the same sort of flow restriction.
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This is one of those counter-intuitive situations where we need to resort to physics. It can be calculated that an adapter of 2" length and 1/4" ID will restrict flow by the same amount as 10" length of 3/8" oil gallery. In other words, it's insignificant. Which begs the question: Why do hot-rod books propose the grub screw method, when the screw-in adapter is so much simpler?
Quote:
Originally Posted by Lynn Eades
This would be a real trap to someone changing the engine use, and would have caused a few "run" rear mains.
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Actually it's the forward bearings which would fail, as the rear main is supplied direct from the pump. Not that it particularly matters! As you say Lynn I'm sure this trap led to catastrophic failures upon engine swap. Again, it begs the question: Why would Aussies booby trap their carrier motors in this way?