About 800 rpm idling. The only way it can get to the backside of the valves is through the guides, intake not sealing or rings. I called total seal and the tech guy told me that for oil to get to the backside of the valves because of ring failure it would be smoking like crazy and the plugs would be covered in oil. So it has to be intake or guides. Intake looks like it is sealing, had it off probably 4 times now.
