Review on 🔌 NGK BKR6E-11 Standard Spark Plug: Reliable Performance in a Universal Size by Kendrick Breezy

The only spark plugs you should use on your Subaru. I have a 2003 Impreza OBS. NGK is top notch. Subaru lists them and the BRK5E-11 as replacements. The difference is in the heat. 5 is a hotter candle and 6 is a colder one. All of these are great for the EJ251. The old candles I had had a 6 rating and they looked normal worn (no knocking or abnormal soot) so I'll probably continue to use 6 heat rated candles. They have the correct spacing of 1.1mm, which suggests -11 in the product name. Subaru recommends a clearance of 1.0 to 1.1 mm. Be sure to check the gaps with a gap tool beforehand, just to be sure. All mine were at 1.1mm so no adjustment was needed.