This thread is about Evo IXs, not Evo VIIIs. Please pay attention to the thread title.

 

I'm guessing this would be for a stock IX.

How about a modded IX, running a Red and 30psi on pump gas?

I'm running the Denso 1 step colder iridiums right now, and I'm getting some nasty misfires (been running them since Dec, gapped at .022, started having issues recently and plan on buying new plugs today or tomorrow). A cheap plug that works to hold me over would be fantastic (even better if they actually work good in my setup).

 

and its full of info about 8 plugs too. I can read!!! I wanted an answer not a smart *** remark.

 

Full bolt on IX with stock turbo (including o2 housing manifold etc)

I'd prefer to run copper plugs and change them out every two oil changes (6-7k miles)

What should I be looking at?

 

Can you elaborate why using a plug with a 6 heat range works good when the stock is 7?

 

anyone?

 

I have these in my car today and all seems okay.Going to examine one after some spirited drives in a couple days. If you(DG) use these in the IX what power levels are you using them to.

 

this is a good thread, bc so many ppl get the wrong impression, thinking Evo 8' plugs will fit Evo 9's and they wont, bc of course the length issue. thanks DONE for this very important info.!

 

We have used these plugs up to 42psi with a dli2 gapped to .022 no misfires on a 650whp evo 9.

 

Wow thats impressive and if that indeed is the case it seems to indicate that colder plugs are maybe not needed. I just worry since plug makers will tell you that running a hotter plug could cause engine damage. Anyway they seem to run very well in my IX and thanks for the info because I would rather run copper than iridium anyday.

 

That is silly....The stock plugs should last you well past 40K miles....

 

Almost time to replace mine... thanks for the info!

 

okay then why do most of the dsm and evo 1-8 users prefer not to iridium? I tell you why iridium sucks as a conductor meaning you lose ignition power and require smaller gaps. Copper is a much better conductor and cheaper hence your wiring in your house. Only silver beats copper and not by much but costs much more.

 

would one step colder plugs benefit me? mods in sig also on 91 pump gas. also what gap ? or just go to the dealer and get them ?

 

What's you hp/tq? If your not having ignition problems leave it. They say after about 100hp over stock go one step colder. Gap depends on your car. What works on some doesn't work on others. On pump gas I did .024, meth .022, SparkTech .028, all one step colder plugs.