This is a subject of many facets and many opinions. My experience is that a stock small block Chevy in good condition will have around ten to fifteen pounds oil pressure at idle when warm, and the pressure will increase with engine speed up to between forty and sixty pounds, and also decrease with engine speed on deceleration. This make some folks uncomfortable, and they go to all sort of lengths to increase the oil pressure. Now, five pounds at idle would seem to be a bit low to me, but not panic time low, just needing some attention. The first thing I would do would be to change the oil and filter, and find another gauge, probably just buy a new one as they are not too costly, to connect in place of the one you have to compare; make sure there are no kinks or flat spots in the tubing going to the gauge, perhaps remove the tubing and clean it and the port in the block out. Depending on how much wear the engine has, it may be worn to the point that clearances are too wide to hold normal pressure at idle. The rings won't have any bearing on oil pressure, but they will contribute to oil usage; worn bearings will have an effect, though - also some form of restriction in the oil passages. Others will have differing opinions, so keep an open mind and consider all that you read here. Several of the members here are full time engine builders, and have many years of experience; me, I just hang out under the proverbial shade tree.

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