Spark Plugs
Burning Brakes
Joined: Mar 2005
Posts: 1,227
Likes: 15
St. Jude Donor '06
There are millions of threads on this and everyone has their own opinion. I just did mine last week and i read tons and each different thread pretty much reads the same:
1. NGK plugs either iridium or copper or GM Iridium (PN 12571164) - from what ive read these 3 plugs are the most common.
2. Plug wires, again, everyone thinks what they bought is the best but its been said time and time again...gm red wires are the best and they are sold at a decent price.
Copper is better for performance (you'll only really see this in high HP or boosted applications) but dont last as long. Iridium has better longevity but under certain circumstances dont provide proper performance.
Service manuals usually say between 0.055 and 0.060 gap, however, its been said that its best to use what the MANUFACTURER of the plug recommends and then make sure the plug is actually gapped to the specification. GM iridiums spec is 0.040 gap and many use this (including myself) and the engine runs great. Others use NGK that are gapped at 0.060 and they run well also.
Unless you are in a high HP boosted app, i suggest just sticking with GM iridium plugs and GM red plug wires...should cost around 90 bucks total
1. NGK plugs either iridium or copper or GM Iridium (PN 12571164) - from what ive read these 3 plugs are the most common.
2. Plug wires, again, everyone thinks what they bought is the best but its been said time and time again...gm red wires are the best and they are sold at a decent price.
Copper is better for performance (you'll only really see this in high HP or boosted applications) but dont last as long. Iridium has better longevity but under certain circumstances dont provide proper performance.
Service manuals usually say between 0.055 and 0.060 gap, however, its been said that its best to use what the MANUFACTURER of the plug recommends and then make sure the plug is actually gapped to the specification. GM iridiums spec is 0.040 gap and many use this (including myself) and the engine runs great. Others use NGK that are gapped at 0.060 and they run well also.
Unless you are in a high HP boosted app, i suggest just sticking with GM iridium plugs and GM red plug wires...should cost around 90 bucks total
Last edited by Stealthy4; Aug 10, 2008 at 07:42 PM.
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Burning Brakes
Joined: Mar 2005
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St. Jude Donor '06
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From: Belleville Il
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AC Delco Iridiums worked well for me. Gene at gmpartshouse.com has very good prices.