[Rev]

I'm confused? How would you know that the oil pressure was "perfect" and that you were not having oil circulation?

The first thing I would do is install a good aftermarket oil pressure gauge. If it shows good oil pressure, And you still think there is no circulation, then pull a valve cover and fire it up momentarily. Oil should spurt out the top of the push rod pocket of the rocker arms. I don't think you're likely to see good pressure and no circulation. Oil filters do have a bypass valve that allows oil circulation in case of a clogged filter.

I never trust those idicator lights anyway, so some good after market gauges would be a sound investment IMHO.

Rev