I just installed MSD 6 and Jeg's hot in cap coil in Proform HEI distributor with medium springs. I pulled the plugs to regap to the recommended .050 and I have about 4000 miles on them. They are AC Delco number fives. The plugs showed little wear but were very white. There was only a brown spot on a small portion of the insulator and a little carbon build up on the thread surface. Timings set at 12 with full vacuum at idle and 34 total. Should I be concerned and is this the right plug?
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