Spark plug AC DELCO or OEM Mazda

Fresh AC Delco copper core plugs are all you need. Start with the stock replacements and go from there.

I just replaced my spark plugs on my 2012 1.4T with the ACDelco 41-121 ones.

I just changed the spark plugs for the first time in like 175, 000 miles

Use only AC DELCO ignition components for GM vehicles, and that includes spark plugs. The factory plugs work perfectly.

AC Delco CR43TS.

Copper plugs are actually the best for performance, precious metals just last far longer.

I'd use the original equipment AC Delco plug. Rockauto has them for $6.31 each, with a $3 per plug rebate offered.

At least with double iridium ACDELCO on the c5. It’s 100k intervals.

Standard replacement CR43TS Delco plugs, and a decent brand of wires. Bosch makes nice wires. Our engines don't exactly tax the ignition system, so if it's functional, you don't stand to gain much.

Bought a set of iridium plugs that were wasted after 15k miles. Amazon gave zero fucks. AC Delco gave zero fucks. The scum bags who sold them changed their name and keep selling.

When I got my S60 (2006, T5) the previous owner had some copper AC Delco plugs made to fit an 850 non turbo in it and I wondered why there was very slow engine response.