Popping while undre boost

[Modb]

Hey so recently my r32 has been popping under boost once its warmed up, but pulls really good when its almost warmed up. So i was wondering if anyone could tell me as to why or if they encountered the same thing.
things i know that are done to the car are;
RB25DET swap (unsure of how good a swap)
Fmic
Blitz metal filter
Apexi AVCR
Nistune
gready Bov
3" Cat back (empty cat)

[Skym]

Probably running a tad too rich up until certain coolant temp. When o2 sensor fails it makes ECU make engine stay richer longer which creates a popping sound from exhaust (popping flames). I would think tune is too rich, sparkplug gaps are too wide (common, should be 0.8mm) or o2 sensor is on the way out (if happens off boost, but on boost you can probably eliminate o2 sensor as a cause). Sometimes it can be BOV related (if atmosphere vented).

[Modb]

it seems to only happen when the cars been running for more then a half an hour, only when im on boost. and i don't have a o2 sensor at the moment, i used the bung for my wideband so i could tune it quickly but i plan on putting the o2 back in soon. But if you watch the wideband it stays at 10.9-11.3 when i get on it, abd it just started to happen after i did some good pulls @14psi.

but ill pick up some new plugs, what are recommended for s1 rb25s?

[Alak]

but ill pick up some new plugs, what are recommended for s1 rb25s?

Copper Plugs. NGK or AC Delco or what have you. Gapped precisely to .8mm. Dont bother with Irdiums or plats or what have you. Just a waste of money on the RB engines.

[Skym]

Copper sparkplugs are said to work best on NA engines, not so much turbocharged engines where they can cause trouble if running a decent amount of boost.

I think it's the same stock sparkplug as RB26, NGK PFR6A-11 (1.1mm gap). PFR7A with 0.8mm gap is the upgrade most run when lean the tune out. But need to read the sparkplug tips to see what's the current condition of the sparkplugs your engine is running.

How to read sparkplug tips -

http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp?mode=nml

If engine is running richer (colder cylinder temps) you run a hotter tip sparkplug, like a 5 or 6. If running leaner (hotter cylinder temps) you run a colder tip (PFR7A).

If running bad sparkplugs (wrong sparkplug gap or heat range), one or two of the coilpacks might have started leaking. That happened on my car and was cylinder 4, 5 coilpacks from memory (common for two coilpacks to fail / start leaking at same time), the rest were ok. Test coilpacks on bench when you have them out to change sparkplugs to make sure they are within specs / not leaking.

[Alak]

I ran the iridiums before and I always had a bit of a miss. Switched over to the copper plugs with a .8mm gap and I've had no problems or misses at 14PSI. I'll see if I can find out the exact ones that Im running. I could even be running the NGK PFR7A as I've changed plugs a couple different times (for tuning purposes). I know I have to re gap them every once in awhile as they wear quickly.