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Pardon. I meant to add my old post above only as a link to my reply to RedHexTex & company's most welcomed info about microns in the below thread, not to start a new thread.
Caramba.

Both pistons and rings have been much improved in recent decades, as have motor oils. A lot of vehicles now have overdrive, too. Bore to stroke ratios affect longevity, too. I believe that durability is best with the stroke just a little longer than the bore size.

This is related to my thread just below this one regarding oil filter micron ratings, and how bypass-type filters have a lower (finer) micron rating.

If you really think about it, all that it takes to transform a full-flow "rock catcher" oil filter that filters all of the oil poorly into a bypass filter that filters some of the oil well is a change in the type of media.

A normal full-flow filter with a coarse filtering media will filter all of the oil, but will only trap larger particles.

If you take that same filter but change the media into a finer media that traps smaller particles, the increased restriction will cause less oil to pass through the filter and more oil to pass through the filter bypass valve. It effectively becomes a bypass-type oil filter.

The engineer in me tends to think that bypass-type oil filters are the better way to go. Medium and heavy-duty Diesels use bypass-type filters because they trap the highly abrasive and yet incredibly small soot particles that cause wear.

However, the pragmatist in me says that all modern gasoline automobiles use full-flow oil filters and last a very long time like that, so perhaps full-flow is better on gasoline engines, somehow.

The best solution would be to use both FF & BP. With an engine not originally equipped with a full flow, adapting one could be a challenge. Adding a bypass filter to most any engine with pressure lubrication is not difficult if you have the necessary parts.

All:

The prior dissertations are quite excellent, technically sound and on point...thanks all...

Just take into account what your ACTUAL low/idle speed oil pressure is and what your peak (1800-3000 rpm) delivered oil pressure is...if you dont have a freshly rebuilt engine (most of us), your pressures may not be at the original "as designed" levels, but are still adequate. In order to not push that adequacy "over the edge" you may want to stick with the original bypass method approach so you dont starve any of those precious babbited bearings, cam follower/dashpot dampers (30's super8 and twelve), etc. You can attach (rubber tube slipped over vehicle's pressure gauge tube line) a cheap harbor freight test oil pressure gauge to conduct a pressure runup test; especially if you are not sure if your dash gauge is accurate (make sure you dont have pressure bleed leaks up to your dash gauge).

On Packard Super8 and Twelves in particular, make sure your oil pressure relief valve/circuit (see the parts book and service manuals) is clean, has good spring action and working/adjusted...they do get gunked up, stick open, allow oil flow-by and your oil pressures will typically read low-but-adequate (5-8 psi at idle...no margin but operable)...sometimes your engine is just that worn out, but those bypass valves do stick more often that you might expect, especially if the engine sat or is not driven regularly.

I prefer catching the big "chunkies" and particulates but preserve lots of flow since the oil passages are sometimes circuitous and can be starved (rearward engine area farthest from the oil pump have long path lengths to get to the device in need of lubrication)...this tends to favor the bypass method with a moderate 10-15 micron filter...even at the expense of letting some of the "tiny" stuff through. IF you are diligent and actually change your oil frequently, you can go with a finer filter in a bypass to hopefully capture the smaller stuff and shed the big "chunkies" to the crankcase bowels which are cleared when you simply drain the oil pan/sump at regular change intervals.

I also recommend that if you have "moderate" oil pressures, add some of our favorite Ju-Ju juices (detergent/solvent oils like Marvel, Seafoam, etc) that people on this forum have discussed elsewhere and do a thorough hot drive (at engine speeds, not idle) flush of your crankcase/oil passages to loosen up/shed some of the gunk that may be part of the aged engine process. Also, on a new-to-you or older rebuild engine, doing further flushing of the emptied crankcase with some motor oil + Marvel/Seafoam to flush out the crap that is adhering to the walls of the crankcase/pan...better yet, remove it once after you acquire it, scrap/flush/brush, reinstall with new gasketing and you can visually convince yourself of the status of the crankcase...After all this progressive flushing THEN change to fresh oil/filters to set a new clean pressure baseline to watch against.

The physics, for once, follow life...as we trade pressure vs progress...from just another nerd engineer who has dealt with high speed aircraft turbomachinery (10,000-80,000 rpm) lubrication...

We have mostly better lubricants (temp vs lubricity durability) in this modern era.

Regarding expensive modern stop/off/restart engine components...the dealer shop technician workforce is being trained more and more to "read a code" and remove/replace major components (i.e. throw parts at a problem vs diagnose root cause). The idea of a more modular engine and just swapping it out may end up being the most COST effective solution in upcoming years (though we are bleaching the brains of younger mechanics by not teaching them to listen to the engine and understand routine diagnostic checks)...most of us grew up when you desired to become an "iron engine whisperer"...not sure anyone gives a hoot anymore...

Instead of throwaway engines, maybe small displacement high output engines with direct injection, titanium block and heads, and ceramic pistons would be better. High efficiency, clean burn, very high compression, lots of power, suitable for exchange/rebuild programs. All valve action could be computer-controlled with individual valve motors and no camshaft. Starter motor could be eliminated on multi-cylinder engines. Might need an NOX catalyst.

Quote:

Are you familiar with the Koenigsegg Tiny Friendly Giant engine? 2.0 L, 3 cylinder, 600 hp, 443 lb-ft of torque.
Koenigsegg Tiny Friendly Giant - DriveTribe YouTube video

For more information on the "no camshaft" tech, see the Freevalve website.