spark fouling?
 

Help me someone. I took out my plugs the other day to inspect them. Been feeling a little low on power lately. The plugs were covered in black soot it looked like. I did some reading on this. Someone correct me or confirm. It stated that this condition was due to spark not reaching full capacity. I plan to replace the platinums with iridium plugs and make a grounding kit for my evo. I read that iridium plugs will fully spark at extreme boost levels and air/fuel levels. Is that true? Is this the correct course of action to take?

Thanks anyone

did you put the platinums in your car, i was always under the assumption that the evo has iridium plugs...

Me too.

Is the car stock. If so it is probably just running very rich.

nastea I believe you are right. I just found this out the other day. Originally I thought that the stock plugs were platinum so I bought a set of one step colder platinum plugs. When I found out that Mitsu sells the stock plugs for around $20 something dollars I realized (guessed) that the stock plugs are iridium.

mojo my car is not stock. I am running stage 1 Vishnu Sig.

Yes the stock plugs are Iridium, they are the NGK BPR6EIX, you can go one step colder BPR7EIX, thats what Im going to use, I also had a bunch of Black build up on my plugs, probably from running so rich-

The stock plugs are iridium. I had the same thing happen to mine. I had some of my mechanic buddies look at the plugs too.

Two words... PIG rich.

I also had a problem with bad gas. It was very easy to identify because I started getting gas at one place exclusively. Trashed my stock plugs about 1000 miles after I started using this place. Trashed another set of NEW plugs after another 1000 miles. The mechanics said I wasn't getting a clean burn which also added to the carbon build up. I put a can of combustion cleaner through the intake and put in HKS iridium plugs. Not a problem since.

Thanks guys, definitely going to get iridium. Where do I order the one stage colder NGKs? I've seen the Densos for sale. I really want NGKs though.

If you go colder, they will foul faster. Stick with 6's till your making a consistent 300+ whp every day.

I guess that's what I will do then. I can always put the stock plugs back in.

Any other opinions?

Is everyone else running stock plugs? Has anyone else experienced this issue? 60 hits and only a few replies. How about some tuners? What spark plugs are you guys running? Heat range? brand? mods?

The stockers are actually heat range 7. (iridium)

You can go with a heat range 8 and still get away with excellent idle. I run the HKS S40G which is grade 8. I check them every so often, and they look perfect. Just a tad bit of burnt browness on them. No det, and no soot at all. Im burning all my fuel {thumbup}

Do a search and youll find many excellent spark plug threads. Most of which youll find DSM babble about copper NGKs. I dont care what anyone says, ive felt power loss from running copper NGK BP8ES and 7ES gapped from hell and back (.024-.028). They just dont compre to iridium at all. You can feel the difference.

The gaps on the Iridiums are smaller than basic copper plugs. The gap should be .023 - .024. All Iridiums come almost perfectly gapped from the manufacturer, so you dont have to dink around trying to gap them yourself. When it comes to running a 20psi street car, dont dick around and get some good plugs.

me too

Yup, definitely going with stock then. Thanks.

I have 15500 miles on the car. I am looking into getting some new plugs also. I know Buschur uses the bpr7es gapped at .032 with great success as he runs an 11.65 on them. I am thinking of giving them a try. My EGT's also will top 900-910 degrees Celcius at 19psi at 7000rpm's. I turned my boost down to 17psi at redline and now I top out at 880 C at 7000rpms. I only have 91 octane. I also looked at my plugs. They look odd if you ask me. I will post a pic up as soon as I get one. I think my ECU is pulling to much timing out causing the high egt's. Maybe I am just forced to run 17psi at redline with this 91 crap.