installing New HEI, spark plug gap - Chevelle Tech
 
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post #1 of 7 (permalink) Old Aug 18th, 19, 10:03 AM Thread Starter
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Mike
 
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installing New HEI, spark plug gap

All,
I am installing a new HEI distributor, new spark plugs also,1972 GMC Sprint, L-48 350., standard ignition called for a .035 spark plug gap, is there any need to change the gap with HEI?, I am using A/C Delco R44 T spark plugs.

Thanks,Mike
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post #2 of 7 (permalink) Old Aug 18th, 19, 11:02 AM
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Tom
 
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Re: installing New HEI, spark plug gap

Dave Ray who helped design the HEI has said .045. I doubt you would see a difference if the gap were .035 or .055.

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post #3 of 7 (permalink) Old Aug 18th, 19, 12:17 PM
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Re: installing New HEI, spark plug gap

.045
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post #4 of 7 (permalink) Old Aug 18th, 19, 7:21 PM
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Eric
 
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Re: installing New HEI, spark plug gap

.045 and your original timing settings will be N/A due to the timing curve of the HEI.

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post #5 of 7 (permalink) Old Aug 18th, 19, 7:34 PM
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Rame
 
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Re: installing New HEI, spark plug gap

Daily driver? Going racing? Hows the fuel in your area? If you are just banging around town with somewhat high octane fuel a 35 gap would be ok and the plugs would last a little longer. What are you looking to do with the car is the question. 8.5.1 compression kinda sucks if all you can get is sh** fuel.

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post #6 of 7 (permalink) Old Aug 19th, 19, 6:47 PM Thread Starter
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Mike
 
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Re: installing New HEI, spark plug gap

Thanks for the answers everyone, I don't get it out of the garage to often, only used for pleasure drives.

Mike
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post #7 of 7 (permalink) Old Aug 25th, 19, 3:38 AM
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Re: installing New HEI, spark plug gap

.045 and R45TS or equivilent plugs. TS have an extended core nose, stay cleaner longer.

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