Caprimanic Your theory question numbers are wrong. .068" is the clearance TOTAL for spring coil bind. This tightness may cause the coils to hit each other on full open. IMO and possibly wrong, I want to match the whole valvetrain to an rpm range. I want a low seat pressure but a spring rate in the 4-500 pound reading for a solid roller to turn 7,500 -8,000 rpms and hold float control. I don't want 400 pounds banging the valve into the valve seat, close it without hammering Camshaft profile has alot to do also with this control issue.
Oiling of motor, Since you have the track bug, going dry sump would be alot better way to go. If the cost is too high then add an accusump (3 quart) to the oiling system to help control oiling pressure on high "g" turns. This way you will always have 30-40 psi going to the motor. The only problem again with this is, the oiling pressure at the gauge IS NOT what you are getting at the other end of the motor. THere are oiling modes like a supply line from the main galley to the back of the block and tie into the lifter galley to help
oil the front or back of a motor. 1.5 extra quarts of
oil helps. The canton pan is better than nothing but you will still get the same problem you have now. I have a Canton on my FE motor and have had no low
oil pressure going around long turns, reason for accusump. Have to make sure you reload the tank before turning off motor. On cool down lap make sure to fill and turn off. Sticker on dash help to remind you. I would also grind smooth the inside of the block or any oil returns to the pan to help get the oil back to oil pan and pickup. I don't beleive in painting inside of motor, tryed it with Gyptal and flakes over time, clogged up and almost killed motor from oil problem.
#2 rod bearing, last to get oil? question answered, if first to get oil bearing clearance too large, metal to metal rubbing. Should hear rod knock about this time. Good luck Rick