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proper spark plugs?

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stickshift69

Probationary Member
22
0
Apr 21, 2006
Dauphin, Manitoba_Canada
Hi there. I did some searching for my answer but couldn't find a good enough answer. Is it o.k. to run a spark plug that is one heat range colder on a car that is close to stock? Also, what is a good plug to run? Is it o.k. to run an Irridum or Platnum plug or should I stay with a resistor type? Good brands? Any help would be great.

thanks:thumb:
 
NGK coppers are the best for our turboed applications. Best part: they're cheap. Expect to pay less than $10 for a set of four.
 
I hate to post a "me too" post but..... UnderPrssureDSM is completely right. Our cars do much better with the coppers than other kinds. I know of people using the other kind with no problems but the coppers are just tried and true.
 
http://www.extremepsi.com/store/customer/home.php?cat=567

I'd only trust the copper NGKs in my car. Forget the iridium ones or platinum or diamond tipped blah blah.....too expensive, & like mentioned above, hasn't established the trust that the copper plugs have. When I first bought my car I tried the Iridium plugs for a month or two..then switched to the copper ones after reading about them on here & how bad iridium plugs were..and I didn't notice any difference. "If it ain't broke, don't fix it"...

BPR6ES's will work just fine for you with the mods you have now. No need to switch to colder plugs just yet.

AND they come with the correct gap already...what more do you want.
 
When I bought my Talon it had NGK resistor spark plugs, and from the part number, they were for the non-turbo only. Also my car was stumbling alot (don't know if it was just the wrong plug or other problem)... But anyways to be safe I replaced them with some $1 Bosch Platinium Plugs.

Worst decision ever.


The stumbling went away for about a week. I checked the plugs when the stumbling came back. The core on Bosch Platinums are pretty small. From what I saw on mine the cores were recessed into the plug a little. The plugs were so covered in red soot (thanks to near useless octane booster I bought in bulk). I got a wire brush and cleaned the plugs. I had to get a pin to pick out the soot on top of the core (I'm gentle).

No stumbling for a few days. But it came back.


I bought 4 OBX Iridium Plugs on eBay for $25. Installed them, Stumbling disappeared. :)

Also, on my '97 Eclipse I had alot of misfiring after a few thousand miles with Bosch Platinums. I replaced them with NGK Iridium plugs... 17k miles later and not a single misfire...

Iridiums may cost a crapload more, but I personally think they are well worth it. I heard people say to not use Iridium's with turbos, but I haven't seen a single claim as to what problems it may cause.
 
a_scobel said:
BPR7ES's will work just fine for you with the mods you have now. No need to switch to colder plugs just yet.
AND they come with the correct gap already...what more do you want.


These are 1 stage colder than stock. Also I have never seen one that dosent need to be gaped for our turbo DSM's. We run a tighter gap than the average car. Also to jccjr1982 I have not heard any thing bad about irodiums other than we prefer to run coppers I have seen a buddy run 900WHP with copper plugs. Just sty as far away from Platinums as you can. Good luck.
 
Just an aside, but I have been impressed with the iridium plugs. Was never a fan of the platinum, but the irids can made a dyno'able difference. They are also becoming popular enough to come down in price.
 
Hands down BPR7ESs, but since you said you already had them sounds like your all set.
 
larsenracing said:
These are 1 stage colder than stock. Also I have never seen one that dosent need to be gaped for our turbo DSM's. We run a tighter gap than the average car. Also to jccjr1982 I have not heard any thing bad about irodiums other than we prefer to run coppers I have seen a buddy run 900WHP with copper plugs. Just sty as far away from Platinums as you can. Good luck.

All the sets of BPR7ES's I've put in already had a gap of .030 out of the box...of course you'd still check them before putting them into your car though.

Piranha451 said:
The gap should be .028 if I am not mistaken. Also, I thought that going with a colder range would be for higher boost applications. Is it alright to use the 7s with the stock turbo?

For having few to none mods, the BPR6ES's will be fine. For mildly modded, I'd run the 7ES's. For heavy modded/high boost cars, 8ES's.

For gapping, the usual range is from .028 to .031. Some people disagree on the gap sizes though..Some people say gap them at .028 even on a stock car, some say to gap them at .030...

Here's what RRE says about their 'racing' NGK plugs (Doesn't say if they're 6ES, 7ES, or 8ES though...):

"Colder plugs will retain less heat between combustion cycles, thereby reducing the tendency toward damaging detonation elevated boost levels. Spark plug gap should be set at .030" for up to 16psi boost. Set at .028" for 17psi and up. "
 
Hrm, my Iridiums are gapped at .032 (what OBX, Denso, and NGK recommends for my car)... but I heard here and in a few other places that it should be .028... Should I regap mine?
 
You should only gap it smaller if have misfire issues.....if you can run .30 and have no misfire or spark blow out then I would keep it. I ran .30 for one day and had terrible misfire in the upper rpm ranges, took them out regapped them to .28 and haven't had a problem since.
 
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