I had the same issue. Motor was built by and experienced HEMI shop. I had the motor sitting on the stand for a couple of years before getting serious about the installation. I wanted to double check everything before installation. I popped the valve covers off and spun the oil pump with the primer hex in the drill. Oil squirted out both L and R rocker mounting plates above the #4 cam journal just like yours. I know that restrictors were installed in the oil galley that goes up to the heads on each side (not sure what size hole). I thought that the plan was to use the spray bars for lubrication. The spray bars on my newer mounting plates on my Barton/T&D setup only have oil holes drilled to lubricate the exhaust rockers. The spray bars on my old mounting plates had holes to oil the intake AND exhaust rockers. I guess there is enough splash to keep the intake rockers lubed and cool so in the newer mounting plates, they did away with the spray bar holes for the intake rockers.

Anyways, I removed the cylinder head bolt where the oil gallery comes up through the head and through the mounting plate. The section of rubber o-ring was missing on both sides. I have the instruction sheet from Barton and it says that there should be a short section of o-ring fitted into the space between the cylinder head washer and the little void created by the round section of the spray bar tube in the mounting plate. The section of o-ring runs parallel to the spraybar and is a little longer that the head bolt washer diameter. When you tighten the head stud nut, the washer squishes the o-ring into the void. The void is only on one side so you only need to add o-ring to one side of the spraybar. I called RBRE and they couldn't tell me the section width of the o-ring off hand but said they would send me some o-ring material for free. I thanked them but said that I would source some o-ring material locally. Home Depot had an o-ring repair pack with several different sizes o-rings (0.060", 0.090", 0.120") in the plumbing section. I tried several different sized until I found one that fit in there the best (0.090"). Each time I tried an o-ring, I torqued the nut, ran the drill motor primer and watched for leak volume. When I found the best o-ring to use, the leak was just a small dribble. Bigger was not better with the o-ring size. The section that gave the smallest leak was the 0.090" diameter in the o-ring pack. I was never able to get a completely leak free setup. Upon further investigation, I realized that somewhere along the line my build switched to pushrod oiling. Maybe the builder was going that way all along but we never discussed that detail. My Comp Elite roller lifters are built for pushrod oiling and the pushrods are hollow so that's the strategy.

I was still concerned with how the rocker mounting plates were orientated. They come as a left and right set but neither of my mounting plate sets have any type of external marking so you can tell which is which. The right side mounting plate has a little relief cut into the underside of the spraybar at the #4 cam journal cylinder head bolt hole in the mounting plate that allows oil to come up through a passage and feed into the spray bar. You can see this by looking at the underside of the plate, through the head bolt hole and looking at the underside of the spraybar. And the left mounting plate has the same relief but it is offset in the other direction from the right side mounting plate. So there is a right side and a left side mounting plate if you want to use spray bar oiling! I was able to use a hook tool to probe that area under the spray bar with the cylinder head stud removed. Sure enough, my mounting plates were on backwards blocking oil to the feeds in the spray bars. I'm really not sure if this was done by accident or on purpose but I'm pushrod oiling. So with the plates on backwards, the oil coming up through the block has nowhere to go. Maybe that's why I was never able to completely eliminate the leak. If I take it apart, I'll change the restrictors in the block to completely block the oil flow. You really have to go through the RBRE rocker setup to understand how all this oiling magic works and how things work with your specific build. They call these engines Hemiroids for a reason

The motor had quite a bit of dyno time on it getting the EFI to learn before I picked it up and there were no signs of excessive heat or other lubrication issues in the valvetrain. I suppose that without the o-ring sections in there, there was lots of oil up in the rocker area but the dyno sheets showed plenty of oil pressure so I imagine that the restrictors in the block were limiting the leak. So in the end it all made sense ... pushrod oiling, no spray bar, mounting plates reversed in orientation to block off the spray bar oiling, restrictors in the block. The only issue was the missing section on o-ring. And while I was trying to figure all this out, I talked to RBRE and they said that pushrod oiling is good with the RBRE/T&D system. They said that sometimes if you are not super careful with cleanliness, it only takes a little fleck of crud to plug one of the pinholes in the spraybar pipes. I believe that the spraybar pipes have minute screw-in plugs on each end but I never tried to remove one and clean inside there. Ok - that's my experience. I can provide pictures of the underside of the rocker mounting plates if you can't figure out what the spraybar feed hole looks like. I have a spare set of mounting plates on the self that were customized and didn't fit my Stage V replacement head rocker pattern so I had to buy a replacement set from RBRE $$$ ouch but it really is a nice setup!!

I found some pictures ... the second one shows the little section of o-ring trapped in there under the washer. Sorry about the rotation ... they show upright in my pictures folder.

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