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Old 01-14-2008, 10:16 AM
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Plug gap with hei?

What spark plug gap are you running with an hei setup? I reset mine from .035 to .045 the other day and was curious what everyone else was doing.
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Old 01-14-2008, 10:34 AM
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I usually run anywhere from .05 to .06 depending on brand and their recommendations.
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Old 01-14-2008, 12:13 PM
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GAP

Quote:
Originally Posted by j20brett
What spark plug gap are you running with an hei setup? I reset mine from .035 to .045 the other day and was curious what everyone else was doing.

Depends on coil output too. With a stock GM HEI unit with 35,000 volts gap is .040-.045. With a better unit like a DUI or Ford with 40,000+ volts
a gap of .050-.055 is about all you need.
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Old 01-14-2008, 12:16 PM
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This unit has a 50,000 volt coil...guess ill bump up the gap again.
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Old 01-14-2008, 12:37 PM
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A typical Chevrolet with a 350 engine used R45TS plugs gapped at .045 from '76 through at least '84. Ford's recommended plug gap was .042-.046 on nearly all of their V8's. Some late 70's to early '80's Oldsmobiles had a .060 gap
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Old 01-14-2008, 12:55 PM
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.043-.045
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Old 01-14-2008, 01:08 PM
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I opened mine up to 0.045 when I went to mpfi and a hot coil, but I think it was already said stock gap is 0.035 to 0.045.
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Old 01-14-2008, 10:59 PM
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I found with my setup .043 works great.
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Old 01-15-2008, 02:05 AM
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Plug Gap

Just remember electron flow is in the path of least resistance!
The rest of ignition system must be up to the task.
I proved that to myself by running too large of a gap.
The coil arced to the neg pole and burnt thru the coil tower.
I wouldn't have believed it if I didn't see it. (BlasterII coil/MSD 6al box+ MSD Super Conductor wires).....(.055 gap)
All you need is a reliable arc, proper AFR, &timing=explosion.
Many including myself have chased our tail
when one of the above
has been assumed correct.
My latest assumed ignition problem(tail chase) turned out to be a combination of a slightly rich AFR
at idle and too much initial advance.
I hate intermittant misfires!
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