I know you don't want to hear this, but hopefully it's not a rear main seal infant mortality issue. How much and what kind of oil are you filling it with? One way to localize a rear of engine leak is to raise the engine to a 30 degree angle or so so the oil is now sitting in the rear of the pan and leave it there for a few days. Check for dripping frequently. If it starts to seep get under the car and try to identify if its from the pan or possibly from the RMS. A RMS leak will likely leave a 'starburst' pattern on the engine side of the crank flange, but you will only see that after some extended driving and checking. I hate engine leaks. Love the car, good luck .

Yes, I don't want to hear that, but I also know it could be a possibility!!:frown:

One guy I talked to had the opinion that if the rear main seal is installed correctly, pressure from the crankcase would only allow it to "push" harder on the main surface? But that doesn't account for a mismatched parting joint.:confused2:

Per the engine builder, I'm running Valvoline VR1 20W-50, 5 quarts in a stock pan.

I will try your "technique" also to see if I can isolate the problem.

I'm also wondering if it might be possible to create enough "suction" with this adjustable PCV valve to overcome oil trying to escape past the pan gasket (if, indeed, it's coming from there!!). I'm also wondering if I can measure crankcase "pressure" through the oil dipstick opening, while closing off any other opening, like the valve cover breather locations?? If, so, what might the correct or acceptable amount be??

I, too, hate oil leaks.......and on a brand new engine to boot!!!

Thanks for your input and the kind words about the "build!!"