swapping spark plugs how much gap?
Thread Starter
Intermediate
Joined: Dec 2016
Posts: 43
Likes: 5
swapping spark plugs how much gap?
I have a 2011 A6 GS that i put headers on and had tuned. the tuner said something along the lines of switching to an iridium plug. I bought some TR55IX plugs, what should they be gapped at?
Drifting
Joined: Apr 2016
Posts: 1,286
Likes: 611
From: DFW Texas
Not stated what plugs that were in your LS3, but iridium plugs were stock ACDelco with .040" gap. The iridium tip is so delicate that they should come pre-gapped @ .040" with a disclaimer not to gap them. You should carefully check each plug to confirm the .040" gap is correct and take any that do not conform back to your retailer for a replacement. If you are not experienced at installing plugs in an aluminum head, torque them to 11 ft lbs. Be careful to NOT over tighten them.
Then go out and run the heck out of that car & have fun!
GD
Then go out and run the heck out of that car & have fun!
GD
Drifting
Joined: Apr 2016
Posts: 1,286
Likes: 611
From: DFW Texas
I checked the NGK website for compatibility and the TR55IX will not fit your LS3. The NGK recommended plug is
GD
NGK 7397 TR5IX Iridium IX Spark Plug
This plug is pre-gapped at .040". You should take the TR55IX back & swap them for the proper plugs. Also, do not remove or replace plugs on your aluminum heads unless they are cold to avoid the plugs seizing or stripping the heads.GD
Thread Starter
Intermediate
Joined: Dec 2016
Posts: 43
Likes: 5
I checked the NGK website for compatibility and the TR55IX will not fit your LS3. The NGK recommended plug is
GD
NGK 7397 TR5IX Iridium IX Spark Plug
This plug is pre-gapped at .040". You should take the TR55IX back & swap them for the proper plugs. Also, do not remove or replace plugs on your aluminum heads unless they are cold to avoid the plugs seizing or stripping the heads.GD
Drifting
Joined: Apr 2016
Posts: 1,286
Likes: 611
From: DFW Texas
Not necessarily, Plugs & wires should last 100K miles. I assumed from your first post that your current plugs are not iridium, so they should be swapped, but your new plugs should last a long time. If your current plug wires are in good shape then keep them & be sure they are securely connected to both the plugs & coils when you change the plugs. These cars frequently loosen the plug wires at the coil, so keep that in mind should you ever develop a misfire. Also, be sure you keep the wires away from your headers as they will burn. You might just put wire socks on them, if you don't already have them.
GD
GD
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