Oil Filter Plate

I did most of the oiling mods listed in the sticky,and I also ported the pump and the passages,and I also opened the passages to my top end some,partly to ease the pressure, mostly to cool my springs,and you know that bolt that holds the plate on; there are two kinds; one with a 3/8 sq drive in the center of it, and the other has a hex around the outside. Guess which one is a restrictor; hyup the sq. drive one. I threw mine out and installed the hex drive. I might even have drilled the center out, but that was 20 years ago so I'm a lil hazy on the details.
The HV pump is a brute. Mine still blew the filter off; I thought the filter was a pos. But every filter I tried was same story. So then I took the 15W40 oil out, and tried a 10W30, and it still ballooned.
Soooooooo, I double-plated, double holed the plates, and end of problem.
And I still run the 10W30.


FWI
in the block, the large oiling passage from the pump has a cup-plug installed to divert the oil to the filter. And the oil then returns to the gallery above the plug. The passage has a step milled into it to stop the plug from going in too deep.
But there is no way to tell if it is in deep enough, except the experience of the installer to feel it stop, as he is driving in the cup. So far no problem; if not installed deep enough it becomes a restrictor to the entire oiling system, but the filter won't blow off and you won't see it on the pressure gauge.
But if the installer manages to drive it in too deep, then the pressure will back up and blow the filter off, and you still won't see it on the gauge, except perhaps if you knew what to look for.
There may be a depth spec for this cup-plug, but I don't recall ever seeing one.
The point is; that if drilling extra holes doesn't cure your plate ballooning, then you may have to dig deeper. If the plug is of the wrong size or type, or installed wrong, you could loose rod bearings, as the rpm goes up.

Furthermore, even with everything perfect, Guess what controls your oilpressure, before it blows the relief valve off; that's right internal clearances; mostly the main and rod bearings. So if you are running a straight 40 or 50 oil, and your clearances are very tight, the pressure is just gonna back up until it blows the relief valve........ and the filter plate could just be a tell-tale fuse.