I also heard good things about the Denso PTJ16R15 standard and the Denso IT16 Iridium, but I don't know for sure.
2003 Z06 Spark Plugs
Race Director
Joined: Nov 2005
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From: Supporting the Corvette Community at Abel Chevrolet in Rio Vista, CA 707-374-6317 Ext.123
St. Jude Donor '08
RICH
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
I would change the stock plugs after the drive home from the dealer, they are junk.
Race Director
Joined: Nov 2005
Posts: 14,553
Likes: 1,549
From: Supporting the Corvette Community at Abel Chevrolet in Rio Vista, CA 707-374-6317 Ext.123
St. Jude Donor '08
But either way we can still be friends tomorrow.
Pro
Joined: Aug 2004
Posts: 575
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From: Richmond Hill Ontario
Mybe I'm wrong but aren't the stock plugs Nippendenso's? I had one changed by the dealer and even though it came in an AC-Delco box it was the same as my original Nippendenso's. There's nothing wrong with these plugs and for that matter, any other plug providing it is the correct heat range for your application. Personally, I don't like having to pay more for the OE plug when there's something else out there that will work just as well for less money. Certainly I wouldn't think about leaving any plug in for more than 20 to 30k's, especially in an aluminum head. I'd rather buy regular plugs and change them more often. My personal choice is Champion.
Le Mans Master
Joined: Dec 2003
Posts: 5,561
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From: Atlanta metro Ga.
I think that we all change our plugs in less than 8-10 years or the question would not be asked in the first place. We only sell 120 or more a month without any problems, but everybody knows somebody who knows somebody that had something happen at some point.
But either way we can still be friends tomorrow.
But either way we can still be friends tomorrow.
The whole issue with the platinum pucks tack-welded to the tip of stock GM plugs is well documented.Shortly after I bought my car with 13K miles on it, I found this site, educated myself to the common pitfalls, went out and pulled the plugs, sure enough 2 of them had lost their pucks. I'm not sure when (if ever) GM changed the plug design, so unless someone can verify they did and when, the best advice is to change them.
As far as the 8~10 years go, we have members here owning 8 year old cars that don't have 20K miles on them.. I dive mine all the time but it would take me (at least) 8 years to put 100K miles on it, so again, my comments stand.
NGK TR55's and a tube of anti-seize is less than 15 bucks. Go for it.
Last edited by Dan_the_C5_Man; Dec 19, 2006 at 02:25 PM.
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Le Mans Master
Joined: Dec 2000
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From: Hot Springs AR
NGK-TR55s. Changed out the stock plugs at 100K, amazingly all the pucks were still in place! 
Compared to my '94 Z-28: when I replaced those plugs at 77K miles (I had just bought the car), 3 of the eight were missing BOTH pucks, 4 of the others were missing one, and one plug still had both on. I think AC Delco must have done something to the manufacturing process, because they've gotten much more consistent in staying on.
I'll be changing out my valve springs (she's about to turn over 150K miles and 3+ years of autox) right after Christmas, and I'm going to drop a fresh set of TR-55s in at the same time. These went 48K miles.
HTH, and have a good one,
Mike
Compared to my '94 Z-28: when I replaced those plugs at 77K miles (I had just bought the car), 3 of the eight were missing BOTH pucks, 4 of the others were missing one, and one plug still had both on. I think AC Delco must have done something to the manufacturing process, because they've gotten much more consistent in staying on.I'll be changing out my valve springs (she's about to turn over 150K miles and 3+ years of autox) right after Christmas, and I'm going to drop a fresh set of TR-55s in at the same time. These went 48K miles.
HTH, and have a good one,
Mike
Thread Starter
Instructor
Joined: Sep 2006
Posts: 180
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From: Murfreesboro TN
Thanks for the info.
I just bought this car w/ 36K on it, and I noticed a slight miss in 3rd gear under hard acceleration.
These are probably the stock plugs, so I figured I'd change them.
I just bought this car w/ 36K on it, and I noticed a slight miss in 3rd gear under hard acceleration.
These are probably the stock plugs, so I figured I'd change them.
