Small block top end oiling with Edelbrock heads

Pulled my 408 out of my Duster yesterday after running a couple of new bests (9.74 and 9.73) as I had low oil pressure at idle and a couple of cylinders with bad leak-down numbers as I had some alcohol carb issues that lead to washing out my ring seal. While I have it apart I am going to drill and tap the oiling hole in my edelbrock heads so I can cut back on the amount of oil getting up top.Thinking i will start out with about a .065-.070 orfis hole. Have any of you guys done this and if so what size feed hole did you end up with?

i'v been told by a few that .060" is plenty.

Thank-you

Rather than drilling and tapping I used to cut short sections of 1/4 inch round stock and drill holes in the stock and drop them into the holes below the rocker shafts in my old iron heads. I don't know any reason why it wouldn't work on Eddies or other aluminum heads as well. The big advantage to this method is the ease of removal in the event you need either more or less oil to the heads. All you need is a magnet or a pick. It's very easy to make up several sizes, sort of like changing carb jets.

I feel if I drill and tap it like I did on the feed lines to my 440-1 heads I will have unlimited adjust-ability. Just remove the shaft and unscrew the drilled set screw so I could go smaller or bigger with the drilled hole in the set screw.

This is something I am looking at doing on my Eddie headed 360. Every time I have torn this motor down I have had good oil pressure etc, but the bearings never look good. It full time oils the rockers and I have it unrestricted and I think my next inspection I will restrict the oil up top and give that a shot. I have always liked all the oil up top because its a street car and I do drag week with it and the valvetrain has always been happy...but bottom end not so much even though I never see any issues on the oil pressure guage.

These are 5/16 ID x .370" od x .700" long, they restrict oil to the shafts (assuming you have .375 holes in your shaft oil feed hole) the same amount...without having to pull the heads. Works great.

also depends on what rockers, I was running HS and I was down to .045 and still had plenty of oil up top.