Plug Gap
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8th Gear
Joined: Mar 2017
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Plug Gap
Does .010 of a gap make a difference in performance of a small block Chevy? I am battling with what to gap plugs at. 1980 motor, mild cam/Holley carb/Offenhauser intake/Hedman headers. MSD high output pointless distributor & coil. Have a big-time miss. What to do. Plugs are NGK gapped @ .045. Help. Wanna Cruise!!!
Zen Vet Master Level VII
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From: Southlake, TX
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
.035 is a very good setting for any high performance engine, regardless of ignition system (Bill has a typo above - he didn't mean .35). If the engine misses at .035, you have other problems and issues to track down...
Lars
Last edited by lars; Mar 27, 2017 at 11:03 PM.
Race Director
Joined: Dec 2004
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From: PARADISE
St. Jude Donor '09-'11-'12-'13-'14
I like .035. I'm running an MSD distributor and box, plugs look great and I have no misses.
Big plug gaps can be hard on the ignition system.
Big plug gaps can be hard on the ignition system.
Last edited by claysmoker; Mar 28, 2017 at 01:04 AM.
Race Director
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That large amount of white smoke, unless it is extremely humid, indicates engine coolant leaking into the exhaust. Pull all the spark plugs and look for one or more that show they are not firing and do a compression test. You may have a blown head gasket or other similar issue.
Racer
Joined: Apr 2016
Posts: 493
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Three or 4 people agreeing on a setting doesn't mean it's right, it just means you all agree, for one reason or another.
I had a similar issue with my big block, and I'm running MSD dist. and 6AL box. I called MSD and talked to a tech. We talked about plug gap, and my individual issue. He gave good guidance on what to do in my case, and it worked just like he said. A call to the manufacturer may be in order, with no offense to anybody's suggestions/experience.
I had a similar issue with my big block, and I'm running MSD dist. and 6AL box. I called MSD and talked to a tech. We talked about plug gap, and my individual issue. He gave good guidance on what to do in my case, and it worked just like he said. A call to the manufacturer may be in order, with no offense to anybody's suggestions/experience.
