Flew my RV yesterday with OAT of 83 deg F - should have cooled really well - No Joy!!  The water was OK but the oil cooling just does not appear to cool any better after all the duct/air flow improvements.  The wedge oil pan did not help either- I guess I did not have oil foaming after all.  My oil level in the wedge pan is 3/4 inch below the 1/2 inch aluminum mounting plate.  Now I'm wondering if my oil system is too flow restrictive.  My oil pressure only reaches 85 psi when the oil is cool and when I'm flying it goes to the lower 60's.  Oil pressure is measured on the adaptor plate where the oil returnes to the engine. 

My oil system is as follows:  I come out of the normal oil outlet - (I have not tapped the lower galley and plumbed the  oil outlet there) - with an An - 10 line to the Mazda (89?) oil cooler.  After the oil cooler, I use An-8 hose from the oil radiator to an aftermarket oil filter housing with the K&N HP 1002 oil filter.    From the oil filter I use An-8 hose to go to the adaptor block on the enigne.  Two pictures of the oil system are attached.  The attached pictures are early pictures before the wiring etc. was in flight ready condition.

The oil cooler is clean and I've removed and checked the oil by-pass thermostat in hot water - it opened at or below 160 Deg F. Anyone know of an easy and accurate way to determine if it is working properlly - maybe check temps. at both ends of the oil radiator as the engine and oil heats up.  Also,  is there an easy way to remove the oil thermostat and seal the bypass hole?