Spark plug NGK or AC DELCO

I run ngk tr6 plugs straight out of the box in my cammed ls1 for $6ish a plug (discounted) i change them more frequently for piece of mind. The car runs mint

I use these in my IE stage 1 MK7. I replace them every 20k, zero issues so far. They could probably go another 10k miles, too, I just replace them early to avoid the ground strap issue that seems to be prevalent.

When I order NGK spark plugs, I get NGK spark plugs, not some copy.

The AC Delco Iridium are fine failing that anything NGK the NGK ruthenium work well. Or the NGK Iridium

I replaced all spark plugs with Genuine Audi NGK plugs and replaced all Ignition Coils as well.

After changing: Idles better and more consistent at 700~800 rpm range. Car drives smoother? Changing spark plugs made it visibly better.

NGKs are my go to’s

Also check the spark plugs, sometimes people are cheap and buy autolites instead of NGK. Cheap plugs from previous owner give me a headache.

I bought a NGK №6 4-pack for 20$ at local parts shop, After the replacement, engine problems began: loss of power, misfires, and severe vibration.

I’m lucky if I get a full 5k miles out of a set of ER10S before one of them shits out and I get a misfire.