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I know you are trying to help. It's hard to show feelings with a key board. I appreciate all of the replies so far, really!
I did not check bore size because of the reason you mentioned. 65 psi was cold idle. At 2200 rpm it was at 75 rpm. I didn't take it up higher than 3500 and it remained at 75. When I raced it with the engine at temp. my oil pressure sets, or sat at, 75-80 psi at 6500 rpm.
With that, what mod would you recommend? I'm leaning toward the one that blocks the oil from #4 to the cam bearing and drill and tap in a restrictor into the main oil galleies for rocker lubrication. If any mods, to me, this one as described in the "Power Adder" section, would work best on a street/strip engine like mine.




i wouldn't block any oil to the top end. the pressures you listed above are fine. we run similar pressures on engines that regularly see 7000+ rpm at the track and get driven hard on the street. it's all about volume, not pressure. open up those main passages so the volume gets to the bearings. you'll be surprised how small some of them are as cast. having the 1/2" pickup is great, but by itself it doesn't help much. you need the other passages opened up for it to be effective. one other thing, replace the rod that spun the bearing, don't repair it. if the one next to it got hot, make sure it's checked out preperly or replace it too. hopefully the rest of the damage isn't too bad.


After rereading my post and the rest of them, PERFORMANCEONLY is spot on IMHO.

Also consider this. Too much viscosity can starve a bearing. I would never use an additive that increases viscosity because the oil engineers know what they are doing, and why. There is a constant loss of pressure as a liquid moves through a tube. Thicken the liquid, and the rate of pressure loss due to friction sky rockets. Sometimes a thinner oil is much better in certain circumstances than thinner oil. Given that a lighter oil will still support the load, you have more capacity (flows easier) and more cooling. But your motor should work just fine with 15w40 if the passages are ok and bearings etc are done right. The restriction I talked about also hurts you on the suction side. Then when the oil is trying to move through the motor there is more loss. Stack everything together and the answer to why the bearings failed is in there somewhere.
An extreme example of what I am talking about with pressure loss happened at the newspaper where I used to work. The ink we pump hundreds of feet to the press is thicker than 600w grease. The engineering study said to run huge (8 inch?) pipe to overcome the friction. Some genius said it cost too much, and reduced the size of the pipe in the plans. Guess what? The presses on the end of the line couldn't get enough ink when the first ones were running.
As far as pressure needed, I run 65 psi at idle cold. Never goes above 65 psi. .0025 rod/.0035 main clearances, 7200 to 7800 rpm at the stripe. No problems. I do run the motor hot, which keeps the viscosity down some.

8..603 156 mph best, 2905 lbs 549, indy 572-13, alky