318 popping in left bank header under load. Look at my plugs

Jeff Seighman said
?????

Jeff

It looks like mud. Tell something you've seen like that before that isn't a million mile motor , exaggerationwith issues.

HankRearden said
Hmm yeah, its definitely popping badly in the exhaust not out the intake.
Starts like fuel injection and idles perfectly. Only does it under load. I wonder if it could have burnt a valve?

Yes. Hung open, under some load will pop out the exhaust. Not at idle, just under throttle. Could be your problem.