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Old 06-02-2012, 10:51 AM   #1
Mikec10
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spark plug gap 350

whats a good spark plug gap for a gen 1 350 with hei ignition?

i keep getting mixed answers from the internet ranging from .030 to .060
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Old 06-02-2012, 10:51 AM   #2
cableguy0
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Re: spark plug gap 350

With HEI its .045
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Old 06-02-2012, 02:12 PM   #3
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Re: spark plug gap 350

Still the same for a mildly built up motor 0.45? I have a edelbrock rpm intake and and edelbrock 600cfm carb. I know it has a cam in it but I could not tell you what kind. Conpresion is a even 180 across all pistons.
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Old 06-02-2012, 02:15 PM   #4
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Re: spark plug gap 350

The only thing that matters for the spark plug gap is the ignition system. .045 is where it needs to be for an HEI. Any larger and the coil and module get overworked and a smaller gap will hurt fuel economy.
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Old 06-02-2012, 02:23 PM   #5
truckdude239
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Re: spark plug gap 350

i set mine at .045
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Old 06-02-2012, 03:14 PM   #6
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Re: spark plug gap 350

X3
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Old 06-02-2012, 04:41 PM   #7
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Re: spark plug gap 350

.045 for HEI.

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Old 06-03-2012, 03:03 PM   #8
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Re: spark plug gap 350

x4
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Old 06-04-2012, 01:21 PM   #9
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Re: spark plug gap 350

R44TS 0.045 gap
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Old 06-05-2012, 11:47 PM   #10
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Re: spark plug gap 350

x6 I run .045 in mine, you can run a little more if you have lower compression (its harder to get a spark at higher cylinder pressures from high compression or boost) or a higher output coil.
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