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You break em, we fix em
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1,266 Posts
Discussion Starter #1
Put em in, they work! Went up from a .028 gap at 18-20 psi to a .035 gap - no blowout. Gonna try larger next time I change the plugs! Hearty 2 thumbs up from me for less than 200 bucks. Mounted them like an ass though, can someone please send me pics of their mounting. I searched and the old posts no longer have pic links that work.
 

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Registered
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155 Posts
coils

where did you guys get them?JC
 

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You break em, we fix em
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1,266 Posts
Discussion Starter #7
Latest update is that I am getting 3 more MPG easy!! I religously monitor my fuel economy, every time I get gas I fill it and reset the trip odometer and calculate. Well I jumped up from 22 MPG to 25 MPG last tank since changing the coils and increasing the gap. In general the exhaust note sounds much better, much smoother and my butt dyno tells me the acceleration is not really much faster but DEFINITELY smoother and more consistant. Before the coils I would occasionally get stumbles or blowout now it is basically nonexistant. I also notice the 'VPC off idle stumble" seems significantly better.

Everyone should buy these things immediately for under 200 bucks it is a TREMENDOUS improvement if you are a high booster suffering from blowout and gapping your plugs down.

Next plug change I'm gonna try stock gap!!!!
 

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Fo Shizzle
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2,410 Posts
Does anyone know the stock part number for NGK coppers?
stock heat range
 

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curt93T/T
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5,079 Posts
Hey omnip_1

So you have to get both numbers(140404 and 140404-s) because one kit comes with two coils and the other just one right? So I also take it that if I got the 140404's I would have to install either the MSD DIS-4 or the HKS ignition system right?
 

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resident evil
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17,080 Posts
I stopped using the NGK platinum R plugs after my first plug change--waste of hard earned money IMHO once you start pushing the boost up cause you have to go in and change them more frequently after that for optimum performance. I love that set-up in the stock location. Moparjim, are you using MSD also?

Sam
 

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Fo Shizzle
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2,410 Posts
brainfood

do these copper plugs fall within the stock heat range?
or are they one or two ranges colder?
 

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OG *** Member
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2,742 Posts
NGK Platinums @ .041 suck. They worked great at first, but after a month of driving it started missing.

I've installed NGK Coppers, two heat ranges colder @ .035. Haven't started the car tho as I have the intake manifold/valve covers off for polishing & doing some body work.

If I remember correctly, the Champion plugs were doing really well at .040+ for shadowfax.
 

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You break em, we fix em
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1,266 Posts
Discussion Starter #17
That NGK number is one range colder I believe and they work great. Champion #71 also work great. platinum or irridium or other plugs are a waste of money and the platinum especially do not work well at higher boost levels, with an MSD, or with nitrous. Search previous rants by me about spark plugs for more info. Nothing works as good as copper, its the best conductor of the bunch. The only advantage to the platinum/irridum is htey are harder and thus last longer. They do not give better performance and usually are worse due to the poorer conductivity and pinpoint electrode designs (to overcome the poorer conductivity. Not to mention coppers are $1.50 each.

If you can't change your plugs AT LEAST once or twice a year, which is well wrth doing in order to check for lean/rich or detonation conditions anyway - sell your sports car and buy a nice Kia that only needs tuneups every 100,000 miles!
 

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Fo Shizzle
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2,410 Posts
the coppers,

how well do they work without an msd or ignition amp?
 

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perpetual college student
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3,903 Posts
omnip_1 said:
here's the stupid little faq i wrote up on ordering, installing, etc. should answer your question hulk.

link
I appreciate the info. What is the site that you purchase them from though? I had a little trouble finding the "checkout". Thanks!!
 
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