i need to find a good plug for my motor. it should be around 410-430flywheel hp. 11.4:1, 109 ls1 cam, and i don't really plan on running nitrous for a lnog time. at least not on these plugs. I currently have the ngk TR6's gapped at .043 (+ or - .002 my gapper is old). i have a miss at lower rpms. i pulled the plugs and only 3 of them were burning right. the rest were all black. i cleaned them and put them back in. same performance. took them out again and they were black again. should i try a different plug, or should i use the tr6's and regap them to something else? i hate to run a hotter plug like the tr55, but i will if it will run great. need some help here. thanks

 

I read a fairly simular post to this the other day, it was recomended to tighten up the gap to .035..why don't you give that a try. Also, with NGK plugs they foul pretty easily from what I have seen, spend a few bucks and grab a new set. See what that does for you.