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Gapping new spark plugs?

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Old Sep 19, 2010 | 12:38 PM
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Default Gapping new spark plugs?
How far should I gap new spark plugs on my 79 vette or does it matter? I bought some standard delcos. Some people say they should be gapped just right and others don't seem to care. I'm just wondering what the general consensus is here on the forum.
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Old Sep 19, 2010 | 01:00 PM
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0.045".
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Old Sep 19, 2010 | 01:01 PM
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it depends on your compression
up to 10.5-- .050-.060
10.5-13.0 -- .040-.050
above 13.0-- .035-.045

at least thats what msd suggests
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Old Sep 19, 2010 | 02:48 PM
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If you still have the HEI ignition system in place and working, .045" gap is recommended. If you have other ignition hardware, it all depends on the components in that system and how much spark potential it is capable of generating. If you have any electronic ignition system and matching coil, .045" is a pretty safe bet. If you converted to a points system, .035" is probably best.
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Old Sep 19, 2010 | 02:51 PM
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Originally Posted by 7T1vette
If you still have the HEI ignition system in place and working, .045" gap is recommended. If you have other ignition hardware, it all depends on the components in that system and how much spark potential it is capable of generating. If you have any electronic ignition system and matching coil, .045" is a pretty safe bet. If you converted to a points system, .035" is probably best.
the 79 im pretty sure is HEI so a .045 would be a safe bet
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Old Sep 20, 2010 | 11:39 PM
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what if I switched to MSD ignition? I have a billet distributor and separate high energy coil (Blaster SS)
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Old Sep 21, 2010 | 08:40 AM
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i havent installed mine yet but i do hear good things about them
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Old Sep 21, 2010 | 10:37 AM
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Originally Posted by Ehardt1979
what if I switched to MSD ignition? I have a billet distributor and separate high energy coil (Blaster SS)
The information with the MSD should list their recommended gap settings.

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Old Sep 21, 2010 | 01:10 PM
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Originally Posted by Easy Mike
The information with the MSD should list their recommended gap settings.

thats where i got this info from

it depends on your compression
up to 10.5-- .050-.060
10.5-13.0 -- .040-.050
above 13.0-- .035-.045

at least thats what msd suggests
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