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      03-10-2026, 01:27 PM   #22
Partee Racing LLC
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Drives: E39 M5, E46 M3, E92 M3, F82 M4
Join Date: Dec 2024
Location: Danville, VA

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Quote:
Originally Posted by charliev68 View Post
Very interesting 🤔
Does that mean that BE and offset ACL bearings are potentially causing insufficient oil clearance and pressure?
As BE's own analysis showed, the extra clearance provided by its bearings dropped oil pressure 3-5 psi. Add to that the periodic oil pressure suck of vanos, and its periodically a larger pressure drop. Set the bearing clearances (both rod AND main) as we do using the old .001" of clearance per inch of journal, and the pressure drop is even greater. Is this the sole cause of failure? Maybe, maybe not. But it contributes. Larger oil wedge required by wider clearances requires more oil, and that means more pressure.

With the SRD gears on one of our strokers, we are seeing steady 80-90 psi oil pressure, but are still breaking the motor in and haven't done any ramp runs yet. Will report back.

--Peter
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