Spark plug NGK or Autolite

It appears you already have a good set of coils, start with plugs, buy good ngk plugs. These engines eat plugs especially once you start throwing boost at them, I’m running one heat range colder than factory in mine right now after smoking a factory spec set but I’m pushing 20psi so your results may vary.

Running the ruthenium plugs. Works good for me FR6AHX-S (94279)

Definitely get NGK’s - the parts store I went with initially gave me other plugs and even with a new DIC the engine was still misfiring without NGK’s

NGK is prob the best sparkplug for performance, Denzo is a cheaper option but there not as good for performance

If you live some where hot, have a tune, or are hard on the car I would do one colder and get the 2309 instead of the stock 7913.

Any correct sized , heat range and gapped NGK plug will work fine but some will need to be changed more often. BKR6EIX for example is a good choice, it is iridium tipped and not expensive.

Always stick with NGK. However, NGK has different lines from copper, to platinum, and iridium. Iridium is more expensive, but will last longer. Given they're a bit of a PITA to replace, I'd go with these. I've run them in my 2004 WRX the last 8 years.

I just installed a set of Iridium XP 6203 in my Optima 2015 and they're working fine. Gap was incorrect on 2 of them, but was easy to fix.

I work on euro cars. If I'm diagnosing an issue that even has me think misfire and it has autolites, I'm done until they're in the trash can and OE is installed.

My experience with auto lite has been complete trash, and their review ratings are always great. Anybody else have problems with auto lite plugs?