I run NGK TR6 plugs they are one range colder than the stock TR5 plug, to go 2 ranges colder you will have to go with an irridium(sp?) plug and that is a TRi7.
I run a gap of 35
With my stock longblock I ran a 13.1 @ 107 with a 1.9 60ft (spinning 60ft btw), the other mods were pullies, 3.73 gears, K&N, and MSD digital6+.
I would rec. the MSD digital6+ as you can set it up to remove timing, how much you want to remove is up to you, when the n2o is activated. That way you can run 14* or so off the bottle and then run a safe amount when spraying. A gen. rule to remember is for every 50hp of n2o remove 2* of timing so with 100hp taking out 4* from your non-ping/det. N/A setup is what you should do. If your still running the stock 10* and have no ping/det. then that "should" be ok. Just make sure you do not have a ping issue.