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Old 11-06-2009, 08:05 PM   #1
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Default What spark plug gap?

I've been searching around and got a lot of answers to the same question

I just bought a set of NGK Power coppers. What should they gap?

So far i've seen people saying .045", .040", .039", .035", .030" and .020". Which one is it? I'm running stock ignition system so i assume the 45 is too much since thats more for COPs.
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Old 11-06-2009, 08:06 PM   #2
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.035-.030"
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Old 11-06-2009, 08:11 PM   #3
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Thank you sir
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Old 11-06-2009, 08:12 PM   #4
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.025 was the most I could run on the stock coil. I run .050 with the Toyota cops. The seemed to blow-out in colder temps, so you may want to take .005 out if its warm out (but you're in Chi-Town so its probably cold).
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Old 11-06-2009, 09:31 PM   #5
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Quote:
Originally Posted by hustler View Post
.025 was the most I could run on the stock coil. I run .050 with the Toyota cops. The seemed to blow-out in colder temps, so you may want to take .005 out if its warm out (but you're in Chi-Town so its probably cold).
This exactly...but my stock coil gaps were closer to 0.020...so I was in a real rush to get COPS.

I run the 0.041 gap with them as they come out of the box.
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Old 11-06-2009, 09:53 PM   #6
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I gapped around .025 @ 14 psi before I got CoP.
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Old 11-06-2009, 10:06 PM   #7
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so wait, its better to go less with the turbo otherwise it blows out?
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Old 11-06-2009, 10:10 PM   #8
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I had my BKR7E's gapped to .030 and they worked great.
You want a smaller gap when turbo'd, yes.
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Old 11-06-2009, 10:13 PM   #9
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unless you have a real ignition system where you can get away with .043" like me on my cheap *** Autolite 3922s
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Old 11-06-2009, 10:19 PM   #10
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Definitely planning to go COP in the future
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Old 11-06-2009, 10:25 PM   #11
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Does anyone at the moment makes COPs to order on here?
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Old 11-06-2009, 10:27 PM   #12
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You have a 90. Brain made a big *** thread about doing it for the earlier years. Just follow that and I don't think youll have problems.

Us NB people don't have a step by step like that. Even though its similar its not the same AFAIK.

oh well
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Old 11-06-2009, 10:31 PM   #13
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i would just like to get a premade one if anyone makes it. I did see the big thread with a step by step how to .
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Old 11-07-2009, 08:34 AM   #14
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Quote:
Originally Posted by triple88a View Post
so wait, its better to go less with the turbo otherwise it blows out?
It's not better, it's a necessary compromise.

Larger gap is "better"...but it can blow out with stock ignition system at boost above about 10psi (for me). I think my coils were getting pretty damn tired at 240K miles...and COPS were like espresso for my motor.
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Old 11-07-2009, 05:38 PM   #15
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What do you guys think? The lower right is number 3... 2nd to the back of the engine

it had some oil on the rim (the washer/gasket) but i dont know if its from when i did the compression test or whatever.

There was no oil on the tip or the threads of the spark plug.

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Last edited by triple88a; 11-07-2009 at 05:55 PM.
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Old 11-07-2009, 09:56 PM   #16
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Looks just a little lean.
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Old 11-07-2009, 10:38 PM   #17
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I'm currently running .020. I tried .025 and got blow-out above 12 psi. Now I'm waiting for my Boundary/WeaponX COPS to arrive .... dreaming of big-gap goodness!!!
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Old 11-07-2009, 10:57 PM   #18
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Quote:
Originally Posted by Rushin View Post
i would just like to get a premade one if anyone makes it. I did see the big thread with a step by step how to .
Just do it man.

I wanted to order some too...and then found all my COPS on eBay for $80 shipped and just started doing it one day...took an afternoon.

The big how to is much shorter when you clip out the parts you don't need.
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Old 11-08-2009, 12:01 PM   #19
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Quote:
Originally Posted by evank View Post
Now I'm waiting for my Boundary/WeaponX COPS to arrive .... dreaming of big-gap goodness!!!
god, how long has that been now?
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Old 11-08-2009, 01:47 PM   #20
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Evan why dont you just toss in a tesla coil in there while you're at it :P
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