Guess The Compression Ratio

moper said

There's an aweful lot of crud on those plugs for pump gas. A lot of oil on the rings too. Can yo urun a new plug or two and post what they look like after a few street miles on pump fuel? It may simply be a matter or changing the ignition curve. You could also have a phasing problem in the distributor. What type of ignition do you run?

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Will do. I already swapped in new plugs when I pulled these ones. I matched the plug #, Autolite AP66. It seems to have temporarily cured the problem. I also put a little less than 5 gallons of 100 octane mixed with maybe 2-3 gallons of 91. The brown on the plugs look almost like rust. Is this possible? Car was not driven often and has maybe less than 5,000 miles.

Ignition looks like stock electronic ignition, Mopar distributor, black control box(when's the last time you've seen one of these?) ballast resistor, and Accel coil.