[KingLT1]

I have run the same LTR7ix plugs on my car for going on 4 seasons with no issues. The only thing I have noticed is a little more cold start misses but it doesn't trigger a code. I think it has more to do with being on Ethanol than the plugs. A friend of mine runs a 7 heat range plug in his H/C LS 4th gen with Nitrous on E85. Also no issues. I wouldn't run a 6 heat range on a Nitrous car unless it's a 100 shot or less. A mild boost setup can get away with a 6 heat range...Jenetty tunes them a little more conservative for those that daily drive their car. If it's a weekend toy and will see frequent WOT pulls put a 7 in it.

My guess is you have something else going on if it's triggering a misfire code. And I also agree with others that the Procharger canned tune is shit.