I mean incorrect fuel mixture, ignition timing, etc

What ignition timing is right? Spark plugs looks nice golden brown. Engine is a hp 500 carb 470 hp from start..

If the tune is too rich it will wash out the cylinders and the rings will never seat. The drop in oil pressure may be from the blow by cavitating the oil pan.

That means nothing if they have been idled on at all.

I started this season with last year's valve cover breathers which were these http://www.summitracing.com/parts/sum-g3400/overview/ They have built in baffle that pretty much almost closes the opening at the bottom. When I ran my motors the first time I got a ton of oil out of the valve covers and dip stick. I've since switched breathers to the K&N open type and no more oil out of dip stick but still get a little out of the breathers.

I too have the same oil pressure condition as you. Pressure drops at higher RPM's. I'm thinking what's happening is what Baja Rooster mentioned above. I don't stay at 5k rpm for long due to this but cruising at 4k around 50mph is no problem

Running a HV oil pump with stock lines will create a similar problem, according to my internet education. The pump opens it's own bypass trying to squeeze high volume through small lines frothing the oil in the pan.

I have all -10 lines and sweeping fittings. Last year, before blowers, oil pressure stayed put but I had a running rich issue and didn't see much above 4500rpm. With the additions of blowers this year and running 5k rpm I have same oil characteristics as the OP.

Not trying to hijack thread, it seems like we are seeing the same issue.

Pushing oil out of the dipstick can only be because of a few different reasons:

1) Not enough crankase venting
2) Too much blowby
3) Way too high of an oil level

And yeh, more blowby would need more venting.

And yeh, they do make disptick assemblies that lock and cannot push out:
http://www.jegs.com/p/Lokar/Lokar-An...23907/10002/-1
Obviously, tht doesn't fix the reason why it's blowing out.

Okay a 4th, but not really a good talk here, or atleast for now, not enough crankcase volume.

maybe because he said this,,,what would you have him do.

Motor needs pulled and taken apart.