My SS just turned over 25,000 miles. I've heard its a good thing to change the plugs out even on a brand new car because the factory gap is at .60 and our cars should be gapped at .45 for optimum performance. Can anyone back that up? What kind of plugs do you guys recommend and what should I gap them at, my mods and dyno numbers are below, doesn't that matter?
Also, I am thinking of installing a TNT wet kit. I've seen a lot of people on here running NGK TR-6's because they are a 'cooler' plug. Would that sparkplug still be a good choice if I wasn't running Nitrous? I'm just wondering if I should go with the NGK 55's for now and then switch or just go ahead and do the tr6's now whil I'm in there.
Finally, what should I gap the sparkplugs at if I am running nitrous? I don't know if I am planning on running a 75, 100 or 150 shot so that does matter right? I'm really curious about this because how is the car going to run the 99.9% of the time that I'm not using the bottle? Someone told me to run the plugs at .45 gap with a 100 shot- and then to gap them .5 more for every 50 hp? So a 200 shot would be .35. Isn't the car going to run bad when not using the bottle at that gap?

 

I have my TR-6's gapped at .035. I run mostly NA and when I have the bottle armed I run 100 hp jets (dry). Excellent performer either way. Hope this helps.

 

Like the Mack Daddy of All Pimps (AKA: BLUBYYOU)
just said, I have always read.. gap the plug at .035