Need help with spark plug gapping
Le Mans Master
Joined: Mar 2002
Posts: 5,955
Likes: 161
From: PNW
Originally, the gap was called out by GM at 0.060", but there was a TSB to dealers and all jobbers that changed the gap to 0.040".
That's why every manufacturer of spark plugs will show the gap to be 0.040" regardless if it's a regular plug, iridium plug or platinum plug.
Tech Contributor
Joined: Jan 2007
Posts: 19,344
Likes: 1,123
From: Dyer, IN
Safety Car
Joined: Jul 2005
Posts: 3,572
Likes: 9
From: Jackson Tn
St. Jude Donor '06-'07-'08-'09
NGK will show that all their plugs applicable to the LS1/LS6 are gapped to 0.040". Go to their website and look up their application tool.
Originally, the gap was called out by GM at 0.060", but there was a TSB to dealers and all jobbers that changed the gap to 0.040".
That's why every manufacturer of spark plugs will show the gap to be 0.040" regardless if it's a regular plug, iridium plug or platinum plug.
Originally, the gap was called out by GM at 0.060", but there was a TSB to dealers and all jobbers that changed the gap to 0.040".
That's why every manufacturer of spark plugs will show the gap to be 0.040" regardless if it's a regular plug, iridium plug or platinum plug.
Thread Starter
Racer
Joined: Feb 2011
Posts: 310
Likes: 9
From: Miami Florida
Thank you guys so much for the help I'm gonna gap the new tr-6's at .40 as I had put some in my car a couple months ago and left them at what they came from from when I opened the box which was .34 and I don't feel my car running right and it also feels like I'm losing power in 3rd gear.
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Tech Contributor
Joined: Jan 2007
Posts: 19,344
Likes: 1,123
From: Dyer, IN
