What spark plugs.....
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Joined: May 2004
Posts: 62
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From: Cedar Park Texas
What spark plugs.....
...are people using out there. I just finished installing my AR Headers that I received from Florida Speed and Performance. Looking at my plugs through my jewelers loupe, they look a little used (44K miles) so i may as well replace them too. Should I just stick to OEM? Any advice?
BTW: I purchased my headers package from Matt over at FSP. Stand up guy there. He did me right on the price, and even though the package was missing two o2 extensions, Matt put them in the mail immediately and I received them the next day. I would definitely do business with them again. I think next time though, I'll pay someone to install them.
BTW: I purchased my headers package from Matt over at FSP. Stand up guy there. He did me right on the price, and even though the package was missing two o2 extensions, Matt put them in the mail immediately and I received them the next day. I would definitely do business with them again. I think next time though, I'll pay someone to install them.
Drifting
Joined: Apr 2006
Posts: 1,278
Likes: 2
From: Lexington TN. Retired Navy
...are people using out there. I just finished installing my AR Headers that I received from Florida Speed and Performance. Looking at my plugs through my jewelers loupe, they look a little used (44K miles) so i may as well replace them too. Should I just stick to OEM? Any advice?
BTW: I purchased my headers package from Matt over at FSP. Stand up guy there. He did me right on the price, and even though the package was missing two o2 extensions, Matt put them in the mail immediately and I received them the next day. I would definitely do business with them again. I think next time though, I'll pay someone to install them.
BTW: I purchased my headers package from Matt over at FSP. Stand up guy there. He did me right on the price, and even though the package was missing two o2 extensions, Matt put them in the mail immediately and I received them the next day. I would definitely do business with them again. I think next time though, I'll pay someone to install them.
Burning Brakes
Joined: Mar 2012
Posts: 836
Likes: 43
From: Killeen Texas
...are people using out there. I just finished installing my AR Headers that I received from Florida Speed and Performance. Looking at my plugs through my jewelers loupe, they look a little used (44K miles) so i may as well replace them too. Should I just stick to OEM? Any advice?
BTW: I purchased my headers package from Matt over at FSP. Stand up guy there. He did me right on the price, and even though the package was missing two o2 extensions, Matt put them in the mail immediately and I received them the next day. I would definitely do business with them again. I think next time though, I'll pay someone to install them.
BTW: I purchased my headers package from Matt over at FSP. Stand up guy there. He did me right on the price, and even though the package was missing two o2 extensions, Matt put them in the mail immediately and I received them the next day. I would definitely do business with them again. I think next time though, I'll pay someone to install them.
I used NGK Iridium TR6 IX Spark Plugs for my 2013 Grand Sport. The mods it has are a Halltech MF103 CAI, 1 7/8" ARH LT headers, 3" catted X, Akrapovic Zo6 mufflers & a tune of course. The spark plugs were the ones that the installer/tuner recommended & the car is running great.
(http://marylandspeed.com/ngk-iridium...-8-p-3559.html)
Last edited by dmoneychris; Aug 30, 2015 at 10:18 PM.
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Joined: May 2004
Posts: 16,667
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From: Raleigh, NC
St. Jude Donor '15
I would go with AC Delco originals. You can go with ZR1 plugs if you want a "6" equivalent.
I (and many others) have had strange things happen voltage wise when running NGK's. Mainly with non iridium versions, though. Many have not had the issue.. it's strange. I just wouldn't bother risking having problems when there are no advantages to be had.
41-110 are the originals
41-104 are the ZR1's that are a step colder
I (and many others) have had strange things happen voltage wise when running NGK's. Mainly with non iridium versions, though. Many have not had the issue.. it's strange. I just wouldn't bother risking having problems when there are no advantages to be had.
41-110 are the originals
41-104 are the ZR1's that are a step colder
Burning Brakes
Joined: Mar 2012
Posts: 836
Likes: 43
From: Killeen Texas
I would go with AC Delco originals. You can go with ZR1 plugs if you want a "6" equivalent.
I (and many others) have had strange things happen voltage wise when running NGK's. Mainly with non iridium versions, though. Many have not had the issue.. it's strange. I just wouldn't bother risking having problems when there are no advantages to be had.
41-110 are the originals
41-104 are the ZR1's that are a step colder
I (and many others) have had strange things happen voltage wise when running NGK's. Mainly with non iridium versions, though. Many have not had the issue.. it's strange. I just wouldn't bother risking having problems when there are no advantages to be had.
41-110 are the originals
41-104 are the ZR1's that are a step colder
-I guess that could be a true statement. I thought & still think that the thing that I noticed was kind of a fluke when;...the DIC showed the statement "Service Electrical System" one time. I brought the topic up with my install guy & he said that the Corvette ECU can get finicky with any slightly different voltage or electrical changes, even plugs. It happened that one time when I first got the new plugs & hasn't happened again.
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Joined: May 2004
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From: Raleigh, NC
St. Jude Donor '15
I've got some screenshots of a log I took with NGK plugs then a log with AC Delco plugs.
I can't explain why.. but the voltage is way more stable now that I put the AC Delco ones back in. Even with the HVAC fan on full blast and radiator fans at 80+%, the voltage still stays in the mid 13's. It used to drop down to low 12's with all of that on when I had the NGK plugs in.
Perhaps I knocked something else around that fixed this issue while I was changing plugs.. who knows. But, I'm happy and will stick with the AC Delco ones. I've heard that they are actually made by Denso. Denso makes some really nice plugs.
NGK's:
AC Delco's:. Notice it's idling LOWER here, and it's still more stable voltage wise
I can't explain why.. but the voltage is way more stable now that I put the AC Delco ones back in. Even with the HVAC fan on full blast and radiator fans at 80+%, the voltage still stays in the mid 13's. It used to drop down to low 12's with all of that on when I had the NGK plugs in.
Perhaps I knocked something else around that fixed this issue while I was changing plugs.. who knows. But, I'm happy and will stick with the AC Delco ones. I've heard that they are actually made by Denso. Denso makes some really nice plugs.
NGK's:
AC Delco's:. Notice it's idling LOWER here, and it's still more stable voltage wise
Burning Brakes
Joined: Dec 2006
Posts: 780
Likes: 9
From: Miami FL
When I got my headers and tune I installed NGK TR55 plugs and have had the voltage problem. It idle it would fluctuate a lot, dip into the low 12's, and the all the lights in the car would flicker. Since replacing them with the stock AC Delco 41-110's all problems are gone. Now at warm idle it never dips below 13.6.
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Race Director
Joined: May 2004
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From: Raleigh, NC
St. Jude Donor '15
When I got my headers and tune I installed NGK TR55 plugs and have had the voltage problem. It idle it would fluctuate a lot, dip into the low 12's, and the all the lights in the car would flicker. Since replacing them with the stock AC Delco 41-110's all problems are gone. Now at warm idle it never dips below 13.6.
Very strange. I can only guess some sort of interference from the plugs? Hell if I know.
I'm just glad this fixed it for me. I was just swapping plugs to swap them while they were out.. I wasn't even trying to fix this issue, it was just a nice side effect
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Joined: May 2004
Posts: 62
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From: Cedar Park Texas
Thanks for all the reply everyone! I went with AC Delco Iridiums. Now that everything is back and I just started, is there any way to really check for leaks in the exhaust system other than just listening for them?
Thats my last step before I take her down off the jack stands.
BTW: The initial starting after the headers upgrade, its not loud enough, I'm sure the added power will be there, but I decided now to buy a performance axle back exhaust set up. A lot of decisions, and then hoping I'm right with my decision on what to buy. A little nervey...
Thats my last step before I take her down off the jack stands.
BTW: The initial starting after the headers upgrade, its not loud enough, I'm sure the added power will be there, but I decided now to buy a performance axle back exhaust set up. A lot of decisions, and then hoping I'm right with my decision on what to buy. A little nervey...
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I've got some screenshots of a log I took with NGK plugs then a log with AC Delco plugs.
I can't explain why.. but the voltage is way more stable now that I put the AC Delco ones back in. Even with the HVAC fan on full blast and radiator fans at 80+%, the voltage still stays in the mid 13's. It used to drop down to low 12's with all of that on when I had the NGK plugs in.
Perhaps I knocked something else around that fixed this issue while I was changing plugs.. who knows. But, I'm happy and will stick with the AC Delco ones. I've heard that they are actually made by Denso. Denso makes some really nice plugs.
NGK's:
AC Delco's:. Notice it's idling LOWER here, and it's still more stable voltage wise
I can't explain why.. but the voltage is way more stable now that I put the AC Delco ones back in. Even with the HVAC fan on full blast and radiator fans at 80+%, the voltage still stays in the mid 13's. It used to drop down to low 12's with all of that on when I had the NGK plugs in.
Perhaps I knocked something else around that fixed this issue while I was changing plugs.. who knows. But, I'm happy and will stick with the AC Delco ones. I've heard that they are actually made by Denso. Denso makes some really nice plugs.
NGK's:
AC Delco's:. Notice it's idling LOWER here, and it's still more stable voltage wise
They've also been known to thrown DTCs in the transmission because of the voltage issues.
OEM are the best.
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Joined: May 2004
Posts: 16,667
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From: Raleigh, NC
St. Jude Donor '15
I do have to say the voltage is higher and more stable than I've ever seen it now that I switched over to OEM ZR1 plugs. I think I'd go with something like Denso as opposed to NGK if I ever needed a colder plug that required going with an aftermarket manufacturer.