Question about Lifter Oil Gallery Plugs

thanks for the input guys, here in Australia i have now talked to quite a few people and Mopar mechanics who say that they have never seen an LA engine WITH the plugs. And i havn't either. So that's weird. We had 273's early on (from the US), some 340's (numbering only about 345 from the US) and mostly 318's and 360's. Many of our blocks came from Canada, South Africa and Mexico and assembly was done here.

I emailed Rick Ehrenberg from Mopar Action magazine about them, he reckoned that the plugs were a late addition only (late 318 and 360), kind of an insurance. But he didn't specify anything else, and i wouldn't take this view as gospel.

Swinger 340, i sort of did what you said, well actually after i drove the plugs in, i then went and checked another block to measure the distance from the front face to the beginning of the oil feed holes. Then measured the depth of the core plugs (including the thickness of the metal) and luckily they will not interfere. But just to be sure, i will use an oil priming rod in the oil pump on the end of a drill through the distributor hole and with the lifters out, i can see if oil is being fed well into the galleries at the front.

As for the timing chain oiling, i wasn't sure which came first, the hole in the bolt method or the tin hat dripper. I have used both in my engine build, can't hurt. There is usually quite a bit of oil in the valley so there should be always plenty oozing out through that bolt. Also, i thought that the lower part of the TC was close or even in, the oil in the pan, especially in street driving when its sloshing around forward and back so i didn't think the chain had too much problems with oil. However if you were sitting at a steady speed for hours at a time and say the oil pan level was a little low, then i could see how the TC might benefit from extra oil. Would better oiling prevent chain stretch though? Maybe if the stretch was a result of wear in the pins rather than the metal itself getting stretched.