MSD and spark plug gap
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
MSD and spark plug gap
OK, I have the MSD 6AL box and wonder what others are gapping their plugs at, factory setting is .035", but the info below suggest that a wider gap is possible
Are you guys gapping mroe than .035"
From the MSD site
Spark Plugs: Choosing the correct spark plug design and heat range is important when trying to get the best performance possible. Since there are so many engine combinations and manufacturers, MSD does not recommend which plug or gap is exactly right for your application. It is recommended to follow the engine builder or manufacturer’s specification for spark plugs. With that, you can then experiment with the plug gap to obtain the best performance. The gap of the plugs can be opened in 0.005" increments, then tested until the best performance is obtained. MSD judges the plug gap by compression and components.
These examples are just starting points to get you going in the right direction. Every application is different and should be tested and tuned.
Are you guys gapping mroe than .035"
From the MSD site
Spark Plugs: Choosing the correct spark plug design and heat range is important when trying to get the best performance possible. Since there are so many engine combinations and manufacturers, MSD does not recommend which plug or gap is exactly right for your application. It is recommended to follow the engine builder or manufacturer’s specification for spark plugs. With that, you can then experiment with the plug gap to obtain the best performance. The gap of the plugs can be opened in 0.005" increments, then tested until the best performance is obtained. MSD judges the plug gap by compression and components.
These examples are just starting points to get you going in the right direction. Every application is different and should be tested and tuned.
Race Director
Joined: Feb 2003
Posts: 18,484
Likes: 1
From: Everyday you must choose between the pain of discipline and the pain of regret. Fredericktown, OH
In my Nova with a 406 (and a 6AL box) I always ran .045. The MSD will make more power in your system allowing a larger gap. However, don't go too big. If you have higher compression or are running N20, you may actually want to go smaller because the increased cylinder pressure can make it harder to light the air/fuel in the combusion chamber.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Originally Posted by Caboboy
It sounds like somebody's getting close! 
barring more snow
, I COULD be on the road!
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Cool, I looks like I can experiment some with this.
