crankcase evacuation?

Ok, I had some time to play with the car friday night and here's what I found. First, I took the breather out and stole the oil fill cap off my challenger and put it in the valve cover instead. Then, I made sure the other valve cover fill cap was tight, and the pcv was as snug as it could be. (The pcv valve is not loose in there, but not extremely tight either). Then, I took my vacuum gauge and put the funnel attachment snugly down in the dipstick tube and showed atmospheric pressure only at idle, no positive pressure or any vacuum. I verified the gauge worked, only slight blowing and sucking on the fitting moved the needle. Then, as I held it in the tube, I revved the engine up to 3-4000 rpm repeatedly and held it there for a few seconds, and no change on the gauge, only atmospheric pressure. Now, obviously the engine wasn't under load like it is when you are driving it, but that's the best I could do for now. So, I am assuming that I do not have any major positive build up going on in the crankcase. I verified the same procedure with the 383 in my chrysler and had the same results. I figured I would have a little vacuum but instead did not have any, although no positive pressure either. Final note, the pcv was sucking good, I checked it later, and my idle vacuum through the pcv hose was 7", but with that big cam I didn't figure it would be any better. Any thoughts?