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Hey guys, I had some trouble with my 22nd series 49... One morning, the lifters sounded a little louder than normal, I placed some oil in, and it began it pretty serious misfire at idle. Took it in for plugs and wires, and nothing... Over read that a head not tightened down could be the culprit... Thoughts??

That is possible, if the gasket is leaking, allowing compressed air and gas to leak from one cylinder to another. A compression test should help check that out. My 39 120 had a terrible misfire or backfire at highway speeds. the culprit, I suspect turned out to be a sticky valve(s) that were not completely closing. The sticky valves problem has been with us since the cars were new, if you read the service manuals. If you start the car, run it until it is hot before shutting it off. Plus I'm a great believer in Marvel Mystery Oil in the gas. The valve on my car stuck for several days until I took it out for a long drive and it finally cleared up.

Is it backing thru the carb, missing/not firing on all 8, or backfiring out the exhaust?
"Lifters" are more prone to stick than valves and valve stay open. They have a shorter guide and take the slapping abuse from the cam especially if not lashed correctly. Valves have springs to close them. The valve seal surface is prone to wear and heat damage and stem warpage but usually only if it's over revved or heated or hit by the piston but that can't happen on an L. The valves are not in/above the combustion chamber per se. A large build up of carbon on the exhaust valve stem can cause aimilar problems, and why I don't like to add oily things to the gas. The "coking reaction" is well known in petrochemical industry. Correcting these are what used to call for a "valve job."
When was last oil change?
How long since last start? More than a week or cold climate?
Do you rev it up when you start cold or allow to warm up?
All these put the valve train at stress. The lack of oil at start causes most engine wear damage.

Refer to section V, page 23-on of the service manual. May want to share with your mechanic.