THE SPARK PLUGS THAT PTUNING SELLS FOR THE TC ARE NOT IRIDIUM, BUT I THOUGHT REPLACEMENT PLUGS FOR THE TC HAD TO BE IRDIUM, CAN ANYONE PLEASE CLARIFY IF I AM WRONG

 

here is a link to the plugs that I am talikng about......

http://www.ptuning.com/html/Item-Des...9&ModelDesc=tC

it seems like a really good deal if they work

 

I bought a set of step 1 colder copper plugs from P-tuning a little while ago, which might be what those are. I think the use of copper plugs are turbo applications is pretty common outside the scion community, but they do not last as long as iridiums (which is why they are cheaper). My roomate used the same ones on his S4 and he changes them every 5k or so. I ended up going back to iridium as I felt I had a rougher idle on the coppers.

 

^^ That pretty much sums it up. From a performance standpoint, the copper and iridium plugs are about the same. The copper plugs will just need to be replaced periodically vs. the iridium plugs which will last a lot longer. Just stay away from platinum plugs - they are designed more for longevity and not performance.

- Toan