NGK Iridium IX Spark Plug (DR8EIX): Outstanding Acceleration & Durability

Recently replaced the long block assembly on a 2005 Mazda3s Hatchback - this being the 2.3 liter non-turbo. carried over all electronics, ...includings plugs :xUnknowingly cracked spark plug # 4 during the motor swap, causing the car to only run on 3 cylinders.Replaced the plugs with cheap-o BOSCH platinums at $2 and change. And when the sales-teenager girl (at a competing parts store... let's call them [@]) stated that they were pre-gapped (according to her trusty computer), I threw them in the car without even checking.The cylinder misfire in #4 was gone, but now I was getting random misfires... causing excess fuel to blow up in my catalytic converter.. my precious, expensive, need-to-pass-emissions catalytic converter.Did a little research, and well, here's the dillie: Mazda uses IRIDIUM spark plugs from the factory. Nothing else. Mazda also uses NGK SPARK PLUGS from the factory. Nothing else. Mazda specified the SPARK PLUG GAP @ .050. Nothing else.****(This only applies to 2005 - 2009 Mazda3s 2.3L motors. The 2004 Mazda3 2.3L had a different ignition setup).****Anyways, I went out, bought these plugs along with a SPARK PLUG GAP TOOL, RE-GAPPED (they were all at .030, made them .050) and installed these plugs. The car started up immediately. During the delightful 106,990 miles I drove the car before oil-starvation lead to a quite unpleasant rod-knock, the car never started this good.And here's to Advanced Auto Parts being the only place that had these plugs. On a Sunday.Thank you Advanced Auto Parts.Lesson learned: Always check your oil so you don't have to go through what I just did.

I have a 2003 Nissan Pathfinder LE and I used this kind of plugs. Within 45,000 miles ran the engine produces smoke on the tailpipe. It was a lot of puzzled that arise within me, considering that the NGK company proclaimed as spark plug world leader!When I let the mechanic changed the plugs they showed it to me, the was in bad shape After, with lot of research, I decided to replaced them and bought the Bosch Iridium. I was convinced with this, due to the bosch video that I watched. It was created in a quality wise. And now I have those in in my engine and I'm fully satisfied, with smooth acceleration, quicker response,improved fuel economy and durability. Finally I would conclude that Bosch Iridium is much better than Ngk Iridium, besides Boch is cheaper than NGK.I'm a happy Bosch Iridium user.