Spark plug Bosch or OEM Subaru

the original spark plugs died (delphi) so i changed them for Bosch ones

We used to put Bosch W7DTC spark plugs in them. No gapping required, smoother idle, and they last 60k miles, maybe more.

You can get NGK or Bosch plugs on rockauto for around $10. Not sure which was OEM, some like NGK for Mercedes in general but Bosch tends to be the OEM maker of plugs for MB.

I recently changed my spark plugs on 2012 Ford Focus. I used Bosch and got a 3 MPG boost.

Since I mounted Bosch 4-prong spark plugs, fuel economy has improved a lot. Gone from 12-13 km/l to nearly 15 km/l.

They're both fine brands, I doubt you'll notice a difference. NGK is most likely OEM for your Civic, but it's not like Bosch is bad, they're OEM in my BMW.

The Neuspeed chips don't perform well at all, and the 2.0's do best with BOSCH FR8DS's.

Don't use Bosch on 90s Toyotas.

I think I just went back and got the Bosch. Couldn’t return either because I jacked up the nips trying to tweak them off ????

Champion is OEM and what we suggest at work, but NGK has never failed us with any application. Bosch is generally terrible and we only use them if it’s a very specific application.