Spark Plug Seats - Tapered or Flat?

[JCole]

I'm finding different information on what plugs fit a 1996 I-4.
The factory manual shows plug pictures with tapered seats. I bought a set of NGK model BKR6EGP (7092) that have tapered seats with no gasket. Amazon lists Bosch FR8DPX plugs for the I-4, which have flat seats with gaskets. O'Reilly sold me the Bosch plugs, which ran poorly and appeared to overheat.
Which is correct?

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According to NGK tech support, the correct plugs (BKR6xxx) have a flat seat with gaskets. I must have been wrong remembering that the NGK supplied plugs with tapered seats. I'm really pleased at how much better the Probe runs now with NGK.

[yellowrob]

Ngk is just fine, Bosch.... enh!!
It's all for multiple applications, use what feels best to you. Just stick with copper core whatever it is.

[unionrdr]

I installed a set of the NGK's like those that came with the car & they seem to work the best. Seems to me they're tapered seats?

[Warrprobe]

I have NGK Platniums and they work fine, smooth running besides the IAC that i need to replace whenever I get the money to do so.

As far as using Bosch electrical? That is sketchy these days, they used to be like Fram then became greedy and cheapened up.