Spark plug change on a C6, is it difficult?
Thread Starter
Race Director
Joined: May 2001
Posts: 15,324
Likes: 2,080
From: Guelph, Ontario
Originally Posted by Black06C6
IMHO without aftermarket mods or a reprogram to the micro P this is not a problem. The micro P, coupled to the knock/temp/02/and other sensors, has enough width in the program parameters to comp for the slight variance afforded by temp swings, octane, and density altitude variance (including hi/lo humidity).
Team Owner
Joined: Dec 2002
Posts: 32,074
Likes: 296
From: San Francisco CA
Originally Posted by Black06C6
IMHO without aftermarket mods or a reprogram to the micro P this is not a problem. The micro P, coupled to the knock/temp/02/and other sensors, has enough width in the program parameters to comp for the slight variance afforded by temp swings, octane, and density altitude variance (including hi/lo humidity). Since the benefit of the iridium/platinum anode/electrode combo is both durability and controlled pin point spark performance, a change to iridium should yield no loss of either HP or MPG.
Although I've not pulled my OEM plugs (my C6 is only 8 mos old with 5900 miles), I'm guessing the folks at GM/Corvette put platinums in from the factory. Most performance engines, those looking for 92 and up octane ratings, from either the US or off-shore, are coming from the factory with platinums now.
For me, the only reason I'd pull my plugs is to check the gap. The folks at the factory are known to miss the hole while inserting the plugs and closing the gap a little when the plug hits the head while trying to find the hole. I also check to see that the anode is centered over the electrode to ensure maximum spark exposure causing consistant fuel/air ignition. Bosch has a nice plug geometry in either their platinum 2 or 4 anode design. For a street engine, no, I do not index the plugs - that's reserved for those that need the max in performance.
Does anyone know what type and brand (AC/Delco would be a 99.9% sure bet) are the OEM plugs?
Although I've not pulled my OEM plugs (my C6 is only 8 mos old with 5900 miles), I'm guessing the folks at GM/Corvette put platinums in from the factory. Most performance engines, those looking for 92 and up octane ratings, from either the US or off-shore, are coming from the factory with platinums now.
For me, the only reason I'd pull my plugs is to check the gap. The folks at the factory are known to miss the hole while inserting the plugs and closing the gap a little when the plug hits the head while trying to find the hole. I also check to see that the anode is centered over the electrode to ensure maximum spark exposure causing consistant fuel/air ignition. Bosch has a nice plug geometry in either their platinum 2 or 4 anode design. For a street engine, no, I do not index the plugs - that's reserved for those that need the max in performance.
Does anyone know what type and brand (AC/Delco would be a 99.9% sure bet) are the OEM plugs?
Instructor
Joined: Apr 2005
Posts: 190
Likes: 0
Originally Posted by LS WON
I thought from the factory it was Iridium plugs?
http://www.sparkplugs.com/sparkplug4...Iridium&mfid=0
Iridium is a precious metal that is 6 times harder and 8 times stronger than platinum, it has a 1,200=F higher melting point than platinum and conducts electricity better. This makes it possible to create the finest wire center electrode ever. Prior till now, spark plug manufacturers have favored platinum for their long life or performance spark plugs due to its high melting point, also the technology did not exist to machine and bond iridium on a spark plug electrode (at least in a cost effective manner). Champion spark plugs have produced iridium industrial and aviation spark plugs since the 1960's, but they still sell for over a hundred dollars per plug. Just now is the technology cost effective to use iridium in a spark plug for automotive applications. The strength, hardness and high melting point of iridium make it very well suited for a fine wire plug. The primary iridium plug manufacturers at this time are Denso with a 0.4mm center electrode, while Champion and NGK have 0.7mm center electrodes. These are the best performance plugs on the market for traditional automotive use and many racing applications. Autolite has introduced an iridium-enhanced plug (the iridium content is too low to call it an iridium plug) we do not consider this in the same class as Denso, NGK or Champion.
SIDENOTE: Thus far the tech's we have spoken with report no problems using iridium plugs with Nitrous.
http://www.sparkplugs.com/pdfs/iri.pdf
Instructor
Joined: Apr 2005
Posts: 190
Likes: 0
Information on New Spark Plugs and Gapping #03-06-04-060 - (10/24/2003)
Information on New Spark Plugs and Gapping
2004 Buick Ranier
2002-2004 Cadillac Escalade, Escalade EXT
2003-2004 Cadillac Escalade ESV
2004 Cadillac CTS-V
1997-2004 Chevrolet Corvette
1998-2002 Chevrolet Camaro
1999-2004 Chevrolet Silverado
2000-2004 Chevrolet Suburban, Tahoe
2002-2004 Chevrolet Avalanche
2003-2004 Chevrolet Express, TrailBlazer
1999-2004 GMC Sierra
2000-2004 GMC Yukon, Yukon XL
2001-2004 GMC Yukon Denali, Yukon XL Denali
2002-2004 GMC Sierra Denali
2003-2004 GMC Envoy XL
1998-2002 Pontiac Firebird
2004 Pontiac GTO
2003-2004 Hummer H2
with 4.8L, 5.3L, 5.7L or 6.0L V-8 Engine (VINs V, P, T, Z, G, S, N, U -- RPOs LR4, LM4, LM7, L59, LS1, LS6, LQ9, LQ4)
A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01mm (0.040 inches) when the spark plug is made. The spark plug gap is set during manufacturing and should not be changed or damage to the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
© Copyright General Motors Corporation. All Rights Reserved.
--------------------------------------------------------------------------------
Document ID# 1396703
found this on the GTO forum
http://www.ls1gto.com/forums/printthread.php?t=3796
Information on New Spark Plugs and Gapping
2004 Buick Ranier
2002-2004 Cadillac Escalade, Escalade EXT
2003-2004 Cadillac Escalade ESV
2004 Cadillac CTS-V
1997-2004 Chevrolet Corvette
1998-2002 Chevrolet Camaro
1999-2004 Chevrolet Silverado
2000-2004 Chevrolet Suburban, Tahoe
2002-2004 Chevrolet Avalanche
2003-2004 Chevrolet Express, TrailBlazer
1999-2004 GMC Sierra
2000-2004 GMC Yukon, Yukon XL
2001-2004 GMC Yukon Denali, Yukon XL Denali
2002-2004 GMC Sierra Denali
2003-2004 GMC Envoy XL
1998-2002 Pontiac Firebird
2004 Pontiac GTO
2003-2004 Hummer H2
with 4.8L, 5.3L, 5.7L or 6.0L V-8 Engine (VINs V, P, T, Z, G, S, N, U -- RPOs LR4, LM4, LM7, L59, LS1, LS6, LQ9, LQ4)
A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01mm (0.040 inches) when the spark plug is made. The spark plug gap is set during manufacturing and should not be changed or damage to the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
© Copyright General Motors Corporation. All Rights Reserved.
--------------------------------------------------------------------------------
Document ID# 1396703
found this on the GTO forum
http://www.ls1gto.com/forums/printthread.php?t=3796
Team Owner
Joined: Dec 2002
Posts: 32,074
Likes: 296
From: San Francisco CA
Originally Posted by yellowc6ohio
The factory plugs are iridium
http://www.sparkplugs.com/sparkplug4...Iridium&mfid=0
Iridium is a precious metal that is 6 times harder and 8 times stronger than platinum, it has a 1,200=F higher melting point than platinum and conducts electricity better. This makes it possible to create the finest wire center electrode ever. Prior till now, spark plug manufacturers have favored platinum for their long life or performance spark plugs due to its high melting point, also the technology did not exist to machine and bond iridium on a spark plug electrode (at least in a cost effective manner). Champion spark plugs have produced iridium industrial and aviation spark plugs since the 1960's, but they still sell for over a hundred dollars per plug. Just now is the technology cost effective to use iridium in a spark plug for automotive applications. The strength, hardness and high melting point of iridium make it very well suited for a fine wire plug. The primary iridium plug manufacturers at this time are Denso with a 0.4mm center electrode, while Champion and NGK have 0.7mm center electrodes. These are the best performance plugs on the market for traditional automotive use and many racing applications. Autolite has introduced an iridium-enhanced plug (the iridium content is too low to call it an iridium plug) we do not consider this in the same class as Denso, NGK or Champion.
SIDENOTE: Thus far the tech's we have spoken with report no problems using iridium plugs with Nitrous.
http://www.sparkplugs.com/pdfs/iri.pdf
http://www.sparkplugs.com/sparkplug4...Iridium&mfid=0
Iridium is a precious metal that is 6 times harder and 8 times stronger than platinum, it has a 1,200=F higher melting point than platinum and conducts electricity better. This makes it possible to create the finest wire center electrode ever. Prior till now, spark plug manufacturers have favored platinum for their long life or performance spark plugs due to its high melting point, also the technology did not exist to machine and bond iridium on a spark plug electrode (at least in a cost effective manner). Champion spark plugs have produced iridium industrial and aviation spark plugs since the 1960's, but they still sell for over a hundred dollars per plug. Just now is the technology cost effective to use iridium in a spark plug for automotive applications. The strength, hardness and high melting point of iridium make it very well suited for a fine wire plug. The primary iridium plug manufacturers at this time are Denso with a 0.4mm center electrode, while Champion and NGK have 0.7mm center electrodes. These are the best performance plugs on the market for traditional automotive use and many racing applications. Autolite has introduced an iridium-enhanced plug (the iridium content is too low to call it an iridium plug) we do not consider this in the same class as Denso, NGK or Champion.
SIDENOTE: Thus far the tech's we have spoken with report no problems using iridium plugs with Nitrous.
http://www.sparkplugs.com/pdfs/iri.pdf
for the info. My car will remain factory stock as far as the engine goes so I shouldn't have to worry.
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Drifting
Joined: Jul 2005
Posts: 1,533
Likes: 0
From: az
Originally Posted by yellowc6ohio
if you are talking about the stock iridium plugs they are gapped at the manufacturing facility. DO NOT try to gap iridium plugs you could break the electrode
