If Rings Don't Seat:

[jhv48]

Thanks for the replies. Here's some further clarification:

Break in oil was used for the first twenty minutes of warm up prior to changing it out for the RP 20w50 XPR and the subsequent dyno pulls.

Bore scope shows good cross hatching in all cylinders. No glazing.

I followed the car down the street and no smokle was evident on accel or decel. On cold startup, when the car has been sitting for a few days, there is a SMALL puff of smoke on initial firing, oil can be smelled but only for a moment. I also pump the throttle once prior to a cold start. Puff could be excess fuel and oil. Hot starts, without pumping the throttle result in zero smoke or oil smell.

Intake manifold was pulled so we could check the backs and stems of the intake valves. No intake gasket malfunction. The stems and backs of the valves looked like new. No oil in the intake runners. PCV working just fine.

Plugs are light brown. No signs of excessive oil.

No oil leaks on garage floor.

Now what? Need some creative thinking. We're out of ideas! Don't want to swap out the rings until we're sure what the problem is. Has to be the rings though, doesn't it?