running ngk iridium 8 at 5000 foot elevation should i stay stock gap?have some backfire on deceleration:dontknow:
that is what i was saying just in a round about way. i think the only spark plug that needs gapped now a days is like a old autolite type plugs if you dare run those in anything. for like old school applications.No, you are right. You aren't suppossed to mess with the gap on them; they are pre-gapped.
Yes, they are. But you should "check" the gap out of the box anyway. Especially if you received your plugs "loose" in the shipping box, like the last set I got from DLP (2 were out of the NGK boxes, bounced loose around the shipping box and the factory gap got messed up in transit). Gap should be .024"-.028" (.6-.7mm). The reason NGK discourages "adjusting" the gap on iridium plugs is that you will most likely either break/damage the center electrode or misalign the ground electrodes to the center electrode. Same goes for multi-ground plugs like the OEM plugs. Again, there is a difference between "checking gap" and "adjusting gap". It is recommended that you always "check" the gap of new plugs. It is not recommended that you "adjust" the gap of iridium and multi-ground plugs. Check NGK's FAQ page on iridium and multi-ground plug gapping... says the same thing. :bigthumbsup:someone please chime in if im wrong here but arent iridiums already gapped per application??