PLUG GAP

Old 08-23-2010, 11:05 AM
  #1  
JEFF69Z28
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Default PLUG GAP

CURIOUS,IS A BIGGER GAP BETTER,WHY DO SOME RUN SMALL GAPS AND OTHERS LARGER GAPS?
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Old 08-24-2010, 09:37 PM
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cepx111
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The wider the gap the more resistance and the harder the ignition has to work to fire the plug.

A smaller or narrower gap will actually have a fatter spark kernel than a plug gapped wider.


On high compression motors on gas I run between .028 .032

Cp
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Old 08-26-2010, 05:54 AM
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JEFF69Z28
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Originally Posted by cepx111
The wider the gap the more resistance and the harder the ignition has to work to fire the plug.

A smaller or narrower gap will actually have a fatter spark kernel than a plug gapped wider.


On high compression motors on gas I run between .028 .032

Cp
I HAVE ABOUT 11.50 TO 11.75 IS 45 TO MUCH
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Old 08-26-2010, 07:23 AM
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chevyfireball
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45? What is your motor? I run 20-25 on a 632 nitrous motor.
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Old 08-26-2010, 07:58 AM
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JEFF69Z28
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Originally Posted by chevyfireball
45? What is your motor? I run 20-25 on a 632 nitrous motor.
.045,GAS MOTOR 406 SBC
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Old 08-26-2010, 10:22 AM
  #6  
zipper06
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I run NGK 8's or 9's with gas or alcohol, if i'm running the V-gaps i set them at .022, gas or alcohol, if i'm running the ES version (flat tip) i set them at .025. All use MSD ignition. In my opinion .045 is way out of range. I know that the old HEI setups GM called for .040/.045, but with multi-spark-discharge aka MSD you'll get much better firing of fuel charge setting them at less than .030.

JMO

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Old 08-26-2010, 06:28 PM
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cncmotorsports
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We see .035 to .040 gap makes peak power on most small blocks. If your using a mag then lower to around .025
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Old 08-27-2010, 02:34 AM
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JEFF69Z28
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HOW COME MSD CALL'S FOR .040-.050? USING A 6AL OR 6AL-2
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Old 08-27-2010, 04:10 AM
  #9  
JEFF69Z28
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Originally Posted by zipper06
I run NGK 8's or 9's with gas or alcohol, if i'm running the V-gaps i set them at .022, gas or alcohol, if i'm running the ES version (flat tip) i set them at .025. All use MSD ignition. In my opinion .045 is way out of range. I know that the old HEI setups GM called for .040/.045, but with multi-spark-discharge aka MSD you'll get much better firing of fuel charge setting them at less than .030.
DO YOU THINK NGK 7'S ARE TO HOT?

JMO

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Old 08-27-2010, 10:15 AM
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zipper06
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I think the 7's are more of a street application on pump gas. i run NGK 8's in my 377" on alcohol, and we run ES8's with a pump gas 468 b/blk shooting 200 shot of nitrous. I run NGK 9's in my blown alcohol sm/blk. I think the 8's would be better for your engine.

JMO

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