I have NGK BKR6EKUB (7969) in my cars, both 986 and 996 and they work fine

Unfortunately, spark plug threads are similar to oil threads. The plugs you purchase will work in your car. It's up to you to note if their performance is perfect or you notice anything off.

I stick with OEM but that doesn't mean I would piss on the iridium plugs.

I've owned an '84 Alfa Spider since 1993. Alfa calls for an OEM plug (loge) is basically no longer available. Alfa also calls out a Champion plug as an alternative. Ive never had luck with the champion plug, yet other Alfa owner swear by them. I've run $1 Autolite copper plugs and had no problems. The 'go to' plug for Alfa's right now is an NGK plug (non iridium). I tried the NGK iridium plug in the Alfa and the car did not run or idle as well as with the other plug.

Point is, my experience is with my car. It isn't wrong but means nothing other than a data point to Spider owners.

Try your plugs...If you like them, great, if not, try something else.

Exactly!


.

This is how my plugs looked @ 30k miles. Looked so good I replaced with the same.


http://986forum.com/forums/uploads02...1656508412.jpg

And "the same" would be?...

Are they Bosches?

Based on the spark plugs selection, is there any difference in terms of performance (I mean actually something felt, like low end torque, not necessarily high end power), or smoothness of the engine.

I started a thread in the Technical subforum, so maybe these two should be merged...

With proper plugs for the application.
Of the proper heat range
Gaped properly.
You will not feel any difference from one make or type of plug to another.

Yes. They are Bosch 4417 platinum +4. They were run in my 2.5L and pulled after 30k

miles @ 110k on the engine. Also for convenience you do not gap the plugs, just inspect

the electrodes for damage before installation.

Great plugs but good luck finding those, or any Bosch Platinums, for any vintage car. Bosch has gone NLA for older cars which is a shame.

Not a fan of NGK or most Japanese parts but these days there are no German counterparts (Thanks Bosch!). Yes, I know the OEM plugs are Bosch but to me those are 70's technology.

It's so strange that in modern times, our selection is so limited. It used to be that there were so many spark plug choices for any car but nowadays, not so much.