Spark plug NGK or OEM Mazda

Ended up getting NGK.

I did the plugs around the same mileage in my 2014 CX-5 (2.5 liter), last April at 65,000 miles. Used the comparable NGK Laser Iridium plugs. Mine had some carbon buildup but all in all, they probably could have went longer.

I use the NGK 1675 and have and factory black coils and haven't had an issue. I have had issues with with other brands.

NKGs are the exact same plug just different label and cheaper, and are much better than the stock plugs.

On NGK s website it says laser iridium (the oem ones) are good for 100k miles.

So far, the OP is on to something. I’m using these plugs and that are great. Next I’m going to try the NGK ZFR6T-11G Copper Nickel. These are OEM for later 2.5 motors. I have early 2.5. I’m curious how these slightly bottler plugs will run and especially since I run premium at all times. I’ll report back. But good find OP. These work great.

The 94553 Iridiums... the tip will last longer, but the gap will widen quicker as the ground electrode does not have a platinum disc on it like the Laser Platinums, so, the Laser Platinums will last longer.

The NGK iridium I mentioned before does not have the correct reach. The website says they are the same, but they are not. I think the database is wrong. When I go back to the copper NGK that does have the correct reach, the car drives better. I had all three in my hand and the iridium is shorter from the end of the threads down (reach). NGK websites say they are the same .75 reach. They are not the same in my hands. The copper plug is. NGK 4435.

NGK literally welded a platinum bar to the ground electrode. Is it going to be really butt dyno noticeable? Probably not. But at least it should last at least twice as long as the BKR7E-IX, since I've noticed after 20,000 miles, my mpg goes to crap. The projected square platinum electrode means wear resistance on the ground electrode, like the factory laser platinum spark plugs (PFR7S8EG) having a platinum wear disc on the ground electrode.

Subaru's like NGK (OEM) spark plugs and O2 sensors, respectively. They run poorly and will even throw codes if other parts are used.