Discrepancies in information on LA and Magnum series oil gallery plugs

NC Engine Builder said
I do not know why your plate has that relief in it. What I DO know, is the galley behind it, has full oil pressure, in fact the passenger side galley is fed directly from the oil pump, and if you look, you will see there is a passage drilled down to the #1 main, and then a passage drilled up from the #1 main that feeds the entire driver side lifter bank. If you leave the plug out, you will dump all your oil pressure out behind that plate, and you will cause a massive leak. And I must be the odd man, I've been doing this for decades, and I've NEVER torn down a smallblock that didn't have those plugs, UNLESS it was rebuilt prior.

I have to agree. A lot of time and theory has been discussed on minimizing the oil hemroging caused by the lifter bores. Cross over tubes, drilled set screws and what not. Only to rely on that plate to seal that? I'm with NC Builder, I install on every one I do. In a stock, low RPM, non performance applications, it would be fine. Start adding RPM, and you want most of the oil on the crank.

I should add, in the years I've torn apart these small blocks, I have seen them both ways. Albeit, most HAD them installed. The core plug kits all have them included anyway.