Quote:
Originally Posted by Desoto291Hemi
I believe the fourth ring helped with oil usage,,,,,but it also helped stabilize the pistons while they were running,,,,kept them more steady in the bore .
At least that’s my feelings .
Tommy
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The fourth ring helped with oil control when one piece oil rings were the norm. Not needed with modern 3 piece oil rings.
As for a ring 'stabilizing the pistons....keeping them more steady in the bore', actually, no! A ring has to float freely in its groove to do its job. A stuck ring will not control oil. A free floating ring (which is what we need) cannot "stabilize" a piston! In reality, the piston stabilizes the ring! The ring has to be held square to the bore or it will not control oil. The piston is what holds the ring in its proper place.
This myth reminds me of another myth: That an engine will not start if all the ring gaps are lined up. Not true! Ring gap is so small compared to the space between ring lands that it does not matter where the gaps are. Besides, rings rotate in their grooves when the engine is running, so the gaps all randomly line up by themselves as the miles go by.