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Spark plugs

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I purchased this car 5 month ago and fixing it and running it, I checked the spark plugs when I first got the car and they were beatup so I put new spark plugs Autolite AR3933 racing same ones The previous owner had put. The gap was around 0.025”, I put the new ones around 0.040”, I just wanted to monitor them while I tune it. i drove the car about 300ish miles and today I took them off to gap them to 0.055” based on online and friends recommendation. See photos below. 7 of them were black on top and one had some oil on it and looked beat up for only 300 miles, now I know I could be running rich and I am working on adjusting that and timing, but does this one spark plug tell me? Anything to worry about? The car has a very aggressive cam and DUI distributor, should I change the spark plugs to another model? Appreciate any help
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