NGK's will improve the burn but not fix the prob. Ken at cycle x suggests using champions to get the mixture right as the show the color of your burn better. but sez to change to NGKs for a cleaner better burn. you just need to play with the setup till you get it right. I am still in the process of tuning my set. got em almost perfect, but I'm sorta picky about getting them perfect. I know what their capable of and just can't leave well enough alone till I have it that way.
Good luck

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