I am looking around and trying to figure out which plugs to run. Right now i have autolite 3926's in it and have run 3924's and 3923's but the 26's stayed clean without detonation. Now i wanted to run an NGK with an unprojected tip but don't know of the heat range or number. They are for my 468 bb with afr heads and i will be running a 200 shot.

a #6 autolite is a hot plug!

Sorry I should Have been more clear that is the plugs i run in the winter, cause it runs so much cooler the 3924 from the summer would not have the ground strap color in the right place during winter and ould foul if it did not fire on the first try. Which it rarely will if it sits more then about a week.

I was going to go to a 3925 but they dont make one.

definately look into the ngk V power racing plugs. id say probably something from 8 to 10 (thats the number right on the plug, btw).
we run an 8 as a warm up or motor pass plug in the 632, and with nitrous we use a 10. a 10 is probably too cold for your motor (really need more info, but just based on the 200 shot). we are around a 600 horse nitrous tune up in the 632 (about 13:1) with the 10's. of course fuel pressure and timing is dialed in and so on, so thats a big part of the picture as well fuel octane, as i'm sure you know.
i'd say, buy a set of 10's and a set of 8 or 9's, run the 10's first and go from there. remember lean is fast but fat keeps it alive (sometimes its hard to remember in the heat of battle ;) )

NGK V Power Racing R5671-9 or R5671-10 the higher the number the colder the plug with NGKs. The R5671-8 would be good for N/A.

I agree, try an NGK racing #8. It is roughly one heat range colder than the Autolite 3923 and does not have a projected tip. I just went the opposite direction in my 383 because the NGK #8 was a hair too cold.

The 3923 is the coldest extended tip in that Autolite series, the NGK is not an extended tip and is also available in a #7 (hotter) if the #8 proves too cold or #9 if it is too hot. I doubt you will need the NGK #7 or #9 the #8 should be pretty close.

The extended tip plugs stay much cleaner for street driving, but you can only get so cold with an extended tip plug . . .

Thanks Guys, ill be getting a set of #8 NGK's and trying it out. I cant wait to get it on the bottle. Everything about the car has been built with nitrous in mind and i'm finnally getting to take advantage of it.

Thanks again