I'm pretty sure it was all in the ignition. I can for sure say that the adjustable rotor was loose and probably bouncing the spark signal at higher rpms. After finding the #4 plug looser than I would have liked, I checked all of the plugs today. 6 of the remaining 7 were loose. I was using a 6 inch ratchet to tighten them so its not like I had a ton of leverage. They weren't loose in the threads loose but barely snug.
I never would have guessed to check the torque on the spark plugs.
Talk about a world of difference. The AFR trims were really having to work for the first couple of miles. MAP readings were way lower. I had a 350 Pontiac in a Lemans with really low miles back in the day. All original with the #48 heads. Talk about a smooth and quiet motor. My 468 is now getting close to that level. Night and day difference.
Thanks to all for the help.
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