EVO All Evo Model Discussion

Spark plug gap?

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Old Jul 22, 2018 | 05:09 AM
  #11  
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You think the "big Sucker " would have anything to do with plug gap?
LOL
The higher the CR the smaller the gap.
If you are stock with the super lean 14 AFR numbers, most any plug will jump 040 and a lot more.
 
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Old Jul 22, 2018 | 05:46 AM
  #12  
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Originally Posted by guido4198
Love the NGK Iridiums just as they come out of the box. Never tried to gap'em.
Not Smart...
 
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Old Jul 22, 2018 | 07:17 AM
  #13  
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I don't understand this thread.

My understanding is that copper (actually gold) as a metal
flows electricity better than any other metal.

Outside/ ambient temperature of whatever metal the spark plug's
is made of I don't see any science of that temp change effecting
electrical flow. Although some say colder environment the better
for electrical circuits.

Easy starting, smoother idle, yes I too would call a performance increase.

New plugs always make an engine "feel" better.

So with many of our co-member stating NGK Iridium plugs are the ones to
install over copper OEM (Champion) I don't understand.

The side electrode and the center electrode size and shape seem to me
as the only variable. Just as indexing, the more spark exposed to the fuel charge
the better.

So to aid my understanding, is the electrode shape/ design what our co-members
are "raving" about?
I just can't believe iridium (platinum etc) over copper metal is the rave.
 
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Old Jul 22, 2018 | 07:58 AM
  #14  
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I have to agree with you Kenny.... Life has consistently shown us that the path of least resistance is usually the easiest to navigate...
 
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Old Jul 23, 2018 | 06:33 AM
  #15  
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For my014 twnk, I switched to ngk irridiums almost instantly. 30k and am hetting ready for anew set.
Gap ‘emat 0.40, sharpie open end and will attept indexing.
I understand the placeent is to point the open end towards the intake. But where I get a little confused if proper torque. Or just go by feel?
 
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Old Jul 23, 2018 | 09:04 AM
  #16  
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In my 1998 FSM, it states to coat the threads of the plugs with engine oil and torque to 18-22ft lbs. I don't think there is any difference in trying to clock the ground strap... Your compressed air and fuel is swirling in the cylinder head like a f7 tornado... Just put them in your not going to change performance...
 
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Old Jul 23, 2018 | 10:45 AM
  #17  
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BPR5ES-11 NGK and at .035" if north of 180 psi ccp.....direct dyno knowledge, from over 2 decades ago.
Shy of that...OE gap, and heat range.
Scott
 
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Old Jul 23, 2018 | 08:16 PM
  #18  
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Originally Posted by Hillsidecycle.com
BPR5ES-11 NGK and at .035" if north of 180 psi ccp.....direct dyno knowledge, from over 2 decades ago.
Shy of that...OE gap, and heat range.
Scott
A 5 would be a fairly hot plug with NGK. Smaller #s are hotter with NGK. 7 or 8 would be normal heat range.
 
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