This is a rather drawn out story, but true, and expensive.......
On my blown 406, the block didn't come drilled for a dipstick. It's a Rodeck 350+ Aluminum block that came out of a sprint car. Rodeck wouldn't even drill it. I had/have a Milodon 7qt drag pad on the motor and was looking for a way to keep an eye on the oil qty. I figured I could run around for one season without, just change the oil a couple of times. Anyway, I decided to go from Pleasanton to Sacramento, only 100 or so miles to the Golden State Nationals. Mind you, I had driven it around Pleasanton quite a bit. Well, I got about 20 miles out of town and she started to rattle the lifters and the oil pressure started to drop. Shut the car off and wait about 30 seconds, I fire her up and away we would go. I got to Manteca which was about 30 additional miles. We had to stop 2 more times. Since I couldn't check the oil, I dumped two more quarts into the pan. We left my buddies house and headed to Sac. We had to stop more times. Now, the drive home, which should of taken 1.5 hours took 6! The next day, I drained the pan, only had 3.5 quarts of oil left out of 7 or 9 depending on how you look at it. The engine never smoked a lot, just a little haze if you were looking real hard. The next winter I freshened the motor and had the valley drilled like a normal SBC for the oil to drain back, and removed a screen that was plugged with epoxy on the drivers side by the rear main cap. I also installed a Steff's sight glass in the oil pan to monitor oil quantity, and had the pan powder coated. Put her back together with the same rings in the same cylinders in the same positions (only 500 miles on them), but with new bearings. I changed the oil at 100 miles and everything seemed good. The oil looked new. After changing the oil things got worse. It was using more oil than before. One night before the Good Guys West Coast Nationals. I was at my buddies house in Brentwood. We dicided to pull the blower, he had a boroscope from work, so we looked down the intake runners an they were soaked/pooled with oil. I had already rerouted the PCV and we felt this wasn't the problem. We then pulled an intake stud out and the threads were completely soaked with oil. The anti seize had been completely washed off the threads. We cleaned up all the intake rocker studs and re-installed them with black RTV. The massive oil issue solved. But, things were still not Kosher. Remember the oil pan powder coat? The pan had trapped glass beads which by now had worked themselves loose and almost destroyed the lower end. Rebuild No. 2, removed the "O" rings in the deck and changed over to Cometic head gaskets and new rings and bearings. Now, everything is *****en and she runs scary awesome. No more leakage!
Keith