Spark plug Denso or OEM Subaru

Spark plugs are only $15 for Denso iridium plugs (providing the longest life) and they take no more than 20 minutes to replace them.

Spark plugs are simple too, just need the proper sockets and swivels. Took me about 45 minutes. That middle plug on passenger side is the toughest, but twisting boot 180 degrees and pulling it out from the front made it a breeze!

If you doing the spark plugs do the coils too. For the spark plugs use Denso 3499 (about 15 dollars each), for the coils use Denso 673-1310, (about 50 dollars each).

Denso work quite well

The plugs EQT recommends are compatible. I’ve been running Denso 5749 plugs for over 10k without issue

i just put the densos in my '17 alltrack with a stage 1 tune and they run noticeably smoother than stock. i gapped them to 0.026" before install. it didn't seem like plugs would be that important for a stage 1 tune so i've been surprised.

Denso always.

I replaced the plugs with DENSO 5358 roughly 10K miles ago.

Ive got the densos twin tips in a vxr at present. One thing i can tell you is they dont like heat!!! i recently had a small coolant leak and they would misfire. pretty low heat resitance i think. work fine on cooler engines.

Had some Denso plugs in my '15 WRX (unaware to me) and the plug in cylinder 2 was fouled within 7k miles and caused a misfire. Turns out the shop that the previous owner took it to for the 60k-mile plug change decided to cheap out. I now have OEM plugs :D