Plug Gap
03-27-2017, 09:39 PM
#1
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!!!
03-27-2017, 10:40 PM
#2
Zen Vet Master Level VII
The following users liked this post:
Hot 71 (03-28-2017)
03-27-2017, 11:02 PM
#3
Tech Contributor
Member Since: Aug 1999
Location: At my Bar drinking and wrenching in Lafayette Colorado
Posts: 13,651
Received 4,913 Likes
on
1,926 Posts
.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; 03-27-2017 at 11:03 PM.
The following users liked this post:
Hot 71 (03-28-2017)
03-28-2017, 01:03 AM
#4
Race Director
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; 03-28-2017 at 01:04 AM.
The following users liked this post:
Hot 71 (03-28-2017)
03-28-2017, 06:53 AM
#5
Plug Gap
Is that possibly why I get white exhaust smoke that is really strong when I first start it up? Thanks for the responses, I wanna get to the bottom of this so I can drive it.
03-28-2017, 10:57 AM
#6
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.
03-28-2017, 11:04 AM
#7
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.
