Spark plug NGK or Denso

The racing plugs from NGK are exceptionally expensive, their standard Iridium plug is great as well. I wouldn't spend the money on the racing plug... I've tracked my car with the standard Iridium plug extensively and had no issues with plug wear etc. I personally feel that the racing plug is just taking more money out of your pocket for no gain/return.

I currently have them installed and gapped at .025. I don't know if they're making a difference or not but the car is running great so I haven't bothered switching back to stock.

I've personally ran these plugs in my car with 40+ psi of boost and lots of ethanol for the past 5 years. Great plugs!

I just switched out a set of Bosch's for the NGK PFR7S8EG's...and to me it's night and day.

I ran those plugs with zero issues for many years on my stage 2+ car gapped at .028.

PFR6Q was equivalent to the stock Bosch plugs. They work fine.

Ik22 is one heat range colder than stock,and I have installed these in many 1.8T & FSI cars from stock/mild tune/heavy modded and worked great.

I used NGK BKR5E-7938 they are awesome plugs, i only paid $14 for mine but i have a friend who pays cost. they are around $80.

im still running the NGK BKR7E's at a .026 gap with 11 psi, they do foul quickly but I plan to keep changing them every oil change.

I have the one sided electrode NGKs and it screwd up my mileage. but it seemed to happen once I switched the spark plugs.