Oil on the electrode side of the spark plugs!

[StephenVA]

The 3199 BKREQUP plugs are the multiprong plugs that were popular in 2000. Every manufacturer spoke about the ability of multiple ground straps (Prongs) would provide long life which they did compared to single ones. Technology moved on to fine wire plugs with center electrodes with precious metals that provide better idle stability/ignitability characteristics for lean conditions, better tip in acceleration, and better fuel economy.

Take a look at the Iridium IX - Part No. BKR6EIX, Stock No 6418, Plug gap .032”

https://ngksparkplugs.com/en/product...um-spark-plugs

[nick325xit 5spd]

Originally Posted by StephenVA

The 3199 BKREQUP plugs are the multiprong plugs that were popular in 2000. Every manufacturer spoke about the ability of multiple ground straps (Prongs) would provide long life which they did compared to single ones. Technology moved on to fine wire plugs with center electrodes with precious metals that provide better idle stability/ignitability characteristics for lean conditions, better tip in acceleration, and better fuel economy.

Take a look at the Iridium IX - Part No. BKR6EIX, Stock No 6418, Plug gap .032”

https://ngksparkplugs.com/en/product...um-spark-plugs

Personally, I prefer to just run the copper plugs (BKR6E) and change them out frequently. Especially on these higher mile cars that probably have some blow by. Long lasting plugs aren't that long lasting when the car makes them crusty.

There are exceptions to this. The S65 in my E90 M3, for example, does knock sensing through the spark plugs through some kind of bizarre sorcery. If you don't keep the plugs fresh (max 30k miles, preferably less), you'll lose a ton of power. And you can't swap to alternate plugs without dyno testing.