After reading many threads on here it seems everyone has different opinions about which plugs are better. Copper vs iridium vs platinum. So my question is who is running copper plugs at around 450hp or up and which plugs are you running? I have a set of autolite coppers (yes I know but they were free) in the supra now that are stock rating. After about a dozen pulls on a mix of low and high boost to dial in boost controller I checked the pulled things apart to check the plugs. I only pulled the first plug and have bad news. The plug tip is broke. It doesn't appear to be melted, looks more like it just snapped. I have found a set of ngk coppers stage 7, which is one stage colder than stock(stage 6) that I can have in hand in about 7-10 business days. I'm curious as to if anyone else here is running these plugs, and if so are you satisfied with them? If not ngk coppers then what coppers and what stage are you running?
Sorry if stage is not the correct term, its the way I've had them described to me and thus how I grew up labeling the hot/cold rating of the plug.
Sorry if stage is not the correct term, its the way I've had them described to me and thus how I grew up labeling the hot/cold rating of the plug.