Thread: which spark plugs is everyone using?

Originally Posted by Fivefingerdeathpunch

Well, you didnt ask for what "mod" level. Though this has been covered many many times.

Stock acdelco iridiums for stock. Copper cores ones modded. Your mod level kinda says what plug to run.

This.

If you're not running a smaller pulley than stock, keep the AC Delco Iridium stockers.

When you start increasing boost with a smaller pulley, you can start thinking about cooler plugs.