sorry but i dont really know what colder plugs are. i just got a set of denso iriduims spark plugs, and are those colder. i was told to run colder plugs when running nitrous. well thanks!!

Colder plugs will have a shorter ceramic center part, to allow the heat to bleed off into the head quicker, too cold and they may foul, wont keep the carbon burned off (probably not a problem with nitrous) too hot and they can ignite the fuel mixture b4 firing, causing detonation, hotter plugs will have a long, skinny center electrode and ceramic insulator. The middle part number on the plug will change with heat range, ( and some brands, the HIGHER the number, the COLDER the plug, Check b4 you buy, ask to see the catalog, there will be a chart in the back.

This post has been edited by 97GTinKC: Oct 16, 2003 - 11:42 AM

so which one are my denso iriduims ????

Denso Iriduims would come in very many different heat temps. Denso Iriduim is the type, not the temp... Every type of every company's plugs come in different heat temps.

Well, wich spark plugs are recomended and how does one know if they have too hot of plugs?

-LBCxGUY+Oct 17, 2003 - 12:50 AM

-edo17982+Oct 20, 2003 - 4:43 PM

The replacements for stock for the ST are IK16. I do not know about the GT though.

yeah mine are ik16...does that make a difference??....the car feels smoother and idles less roughly....so the ik16 arent colder or hotter???