Spark plugs
Thread Starter
Advanced
Joined: Jun 2016
Posts: 76
Likes: 16
From: Chicago IL
Spark plugs
Hi everyone
im looking for a spark plug recommendation
Let me start out by saying, yes! I’ve used the search button and found tons of posts on spark plugs. But that being said.... I haven’t found an answer
My car is 07 base supercharged, full exhaust, cam, , forged flat top pistons,meth injection, fuel system etc. should be knocking on the door of 700whp.
Fired it up on the base “drive ability” tune from my tuner and have been fighting my service charging system light ever sinc. Voltage at idle is all over the place. Don’t matter if it’s hot or cold from 11.8 to 14.3
battery is brand new, replaced the alternator checked the wires and terminals at the starter everything clean, tight, terminals are solid also.
I installed the Br7ef plugs. (Brand new and gapped then to .030) I’m thinking that this is my problem. After reading the other posts and even seeing GMs service bulletin about aftermarket plugs I want to try changing them...... But what do I change them to? In most of the other posts everyone says NGK-tr6 but people have issues with those as well
I would like to try the stock ls9 plugs 41-104 but I’m thinking that is going to be to hot of a plug for 700wheel
i would love to just tell the tuner to turn off the code but My voltage is low, interior lights will dim so I know I got to fix it.
does anyone have any suggestions or experience on what plugs I can use
im looking for a spark plug recommendation
Let me start out by saying, yes! I’ve used the search button and found tons of posts on spark plugs. But that being said.... I haven’t found an answer
My car is 07 base supercharged, full exhaust, cam, , forged flat top pistons,meth injection, fuel system etc. should be knocking on the door of 700whp.
Fired it up on the base “drive ability” tune from my tuner and have been fighting my service charging system light ever sinc. Voltage at idle is all over the place. Don’t matter if it’s hot or cold from 11.8 to 14.3
battery is brand new, replaced the alternator checked the wires and terminals at the starter everything clean, tight, terminals are solid also.
I installed the Br7ef plugs. (Brand new and gapped then to .030) I’m thinking that this is my problem. After reading the other posts and even seeing GMs service bulletin about aftermarket plugs I want to try changing them...... But what do I change them to? In most of the other posts everyone says NGK-tr6 but people have issues with those as well
I would like to try the stock ls9 plugs 41-104 but I’m thinking that is going to be to hot of a plug for 700wheel
i would love to just tell the tuner to turn off the code but My voltage is low, interior lights will dim so I know I got to fix it.
does anyone have any suggestions or experience on what plugs I can use
Thread Starter
Advanced
Joined: Jun 2016
Posts: 76
Likes: 16
From: Chicago IL
Oh and one other thing, I’m not sure if this will effect what heat range spark plugs I need. This car is driven on the street only, mainly cruising with a pull or 2. It will never be put on a circuit track. I may go to a test n tune night at the drag strip once or twice.
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,629
As you have figured out, the oem spark plugs are resitor type, and have a high resitance to both them, and the spark plug wires to prevent RF noise feed back through the coils to the ECM, which the ECM controlling the output voltage of the alternator. The worse the ECM RF noise, the lower the alternator voltage out put will be.
As for checking alternator output voltage, use the rear terminal of it under the rubber boot as the positive source for the meter, and the body of the alternator as your negative source. The voltage out put of the alternator with the motor cold and A/C off so the radiator fan is not running, and driving lights off, should be 14.7 volts.
Now lets touch on after market parts on the car, and even if the voltage is 14.7 volts to start with, if you a dual fan set up , and even drawing more power for other items like HP fuel pumps, this could be putting a strain on the OEM alternator that it can not keep up instead. Also may be using an under drive HB, this is spinning the alternator slower at idle, and going to cause problems as well.
As for checking alternator output voltage, use the rear terminal of it under the rubber boot as the positive source for the meter, and the body of the alternator as your negative source. The voltage out put of the alternator with the motor cold and A/C off so the radiator fan is not running, and driving lights off, should be 14.7 volts.
Now lets touch on after market parts on the car, and even if the voltage is 14.7 volts to start with, if you a dual fan set up , and even drawing more power for other items like HP fuel pumps, this could be putting a strain on the OEM alternator that it can not keep up instead. Also may be using an under drive HB, this is spinning the alternator slower at idle, and going to cause problems as well.
Safety Car
Joined: Nov 2007
Posts: 4,435
Likes: 874
From: Bay Area CA
On my 2008 S/C LS3, I have been using NGK TR7IX #3690 gapped at .032 for years with no issues. They are two steps colder than stock LS3 and I replace them once a year.
Last edited by Mike's LS3; Sep 1, 2018 at 11:21 AM.
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
Hi everyone
im looking for a spark plug recommendation
Let me start out by saying, yes! I’ve used the search button and found tons of posts on spark plugs. But that being said.... I haven’t found an answer
My car is 07 base supercharged, full exhaust, cam, , forged flat top pistons,meth injection, fuel system etc. should be knocking on the door of 700whp.
Fired it up on the base “drive ability” tune from my tuner and have been fighting my service charging system light ever sinc. Voltage at idle is all over the place. Don’t matter if it’s hot or cold from 11.8 to 14.3
battery is brand new, replaced the alternator checked the wires and terminals at the starter everything clean, tight, terminals are solid also.
I installed the Br7ef plugs. (Brand new and gapped then to .030) I’m thinking that this is my problem. After reading the other posts and even seeing GMs service bulletin about aftermarket plugs I want to try changing them...... But what do I change them to? In most of the other posts everyone says NGK-tr6 but people have issues with those as well
I would like to try the stock ls9 plugs 41-104 but I’m thinking that is going to be to hot of a plug for 700wheel
i would love to just tell the tuner to turn off the code but My voltage is low, interior lights will dim so I know I got to fix it.
does anyone have any suggestions or experience on what plugs I can use
im looking for a spark plug recommendation
Let me start out by saying, yes! I’ve used the search button and found tons of posts on spark plugs. But that being said.... I haven’t found an answer
My car is 07 base supercharged, full exhaust, cam, , forged flat top pistons,meth injection, fuel system etc. should be knocking on the door of 700whp.
Fired it up on the base “drive ability” tune from my tuner and have been fighting my service charging system light ever sinc. Voltage at idle is all over the place. Don’t matter if it’s hot or cold from 11.8 to 14.3
battery is brand new, replaced the alternator checked the wires and terminals at the starter everything clean, tight, terminals are solid also.
I installed the Br7ef plugs. (Brand new and gapped then to .030) I’m thinking that this is my problem. After reading the other posts and even seeing GMs service bulletin about aftermarket plugs I want to try changing them...... But what do I change them to? In most of the other posts everyone says NGK-tr6 but people have issues with those as well
I would like to try the stock ls9 plugs 41-104 but I’m thinking that is going to be to hot of a plug for 700wheel
i would love to just tell the tuner to turn off the code but My voltage is low, interior lights will dim so I know I got to fix it.
does anyone have any suggestions or experience on what plugs I can use
Last edited by irok; Sep 7, 2018 at 09:40 AM.
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,685
From: Southeast TX
Use the AC Delco 41-110 plugs if you want to find something that works with no issues. If you want to keep chasing gremlins, install a set of NGK TR6's. Same heat range. Just a crap shoot whether they will work or not. They haven't worked for me. Yeah, they are cheap....
Thread Starter
Advanced
Joined: Jun 2016
Posts: 76
Likes: 16
From: Chicago IL
Guys I appreciate the replies.
I ended up taking the alternator wire and standing it straight up. The service charging system warning is still on but the voltage fluctuation seemed to settle down quite a bit. I had it idling for about 40 minutes today with the headlights on blower on high and voltage was hanging out in the mid 13s it would bounce around a little but a lot better. When temp got around 200 and the fan really started working voltage dropped to the low 13s and would dip into the high 12s but then come back to low 13s
for now im going to leave it, until the tunner is done with it. From my understanding he should be able to adjust the idle charging characteristics. So we will see what happens. My appointment is set up for the end of the week I’ll keep you posted
I ended up taking the alternator wire and standing it straight up. The service charging system warning is still on but the voltage fluctuation seemed to settle down quite a bit. I had it idling for about 40 minutes today with the headlights on blower on high and voltage was hanging out in the mid 13s it would bounce around a little but a lot better. When temp got around 200 and the fan really started working voltage dropped to the low 13s and would dip into the high 12s but then come back to low 13s
for now im going to leave it, until the tunner is done with it. From my understanding he should be able to adjust the idle charging characteristics. So we will see what happens. My appointment is set up for the end of the week I’ll keep you posted
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
Guys I appreciate the replies.
I ended up taking the alternator wire and standing it straight up. The service charging system warning is still on but the voltage fluctuation seemed to settle down quite a bit. I had it idling for about 40 minutes today with the headlights on blower on high and voltage was hanging out in the mid 13s it would bounce around a little but a lot better. When temp got around 200 and the fan really started working voltage dropped to the low 13s and would dip into the high 12s but then come back to low 13s
for now im going to leave it, until the tunner is done with it. From my understanding he should be able to adjust the idle charging characteristics. So we will see what happens. My appointment is set up for the end of the week I’ll keep you posted
I ended up taking the alternator wire and standing it straight up. The service charging system warning is still on but the voltage fluctuation seemed to settle down quite a bit. I had it idling for about 40 minutes today with the headlights on blower on high and voltage was hanging out in the mid 13s it would bounce around a little but a lot better. When temp got around 200 and the fan really started working voltage dropped to the low 13s and would dip into the high 12s but then come back to low 13s
for now im going to leave it, until the tunner is done with it. From my understanding he should be able to adjust the idle charging characteristics. So we will see what happens. My appointment is set up for the end of the week I’ll keep you posted
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Safety Car
Joined: Nov 2007
Posts: 4,435
Likes: 874
From: Bay Area CA
Use the AC Delco 41-110 plugs if you want to find something that works with no issues. If you want to keep chasing gremlins, install a set of NGK TR6's. Same heat range. Just a crap shoot whether they will work or not. They haven't worked for me. Yeah, they are cheap....
I agree with Irok, put in fresh plugs before tune to prevent KR and issues during the tune.
Last edited by Mike's LS3; Sep 2, 2018 at 12:53 PM.
Thread Starter
Advanced
Joined: Jun 2016
Posts: 76
Likes: 16
From: Chicago IL
Too hot of a plug with 700 HP! Whichever plug works for him, he needs to be two steps colder than stock. NGK IX7 are iridium and have a projected tip like the stock plugs, but two steps colder.
I agree with Irok, put in fresh plugs before tune to prevent KR and issues during the tune.
I agree with Irok, put in fresh plugs before tune to prevent KR and issues during the tune.
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
Is that where the whole problem comes from? The NGKs with the copper cores or what ever,switching back to an iridium plug should take care of it? I’m understanding that the problem is with RFI but I just don’t enderstand how/why. Do I need just to put an iridium plug back in? Or just a protruded tip plug back in? Or do I need to get away from NGK plugs all together? I’ll buy what ever but I don’t wanna just be randomly buying sets of spark plugs and not have them fix my issue you know.
Safety Car
Joined: Nov 2007
Posts: 4,435
Likes: 874
From: Bay Area CA
Is that where the whole problem comes from? The NGKs with the copper cores or what ever,switching back to an iridium plug should take care of it? I’m understanding that the problem is with RFI but I just don’t enderstand how/why. Do I need just to put an iridium plug back in? Or just a protruded tip plug back in? Or do I need to get away from NGK plugs all together? I’ll buy what ever but I don’t wanna just be randomly buying sets of spark plugs and not have them fix my issue you know.
Last edited by Mike's LS3; Sep 3, 2018 at 12:53 PM.
Thread Starter
Advanced
Joined: Jun 2016
Posts: 76
Likes: 16
From: Chicago IL
I don’t know either, it’s really frustrating though. I just spent $70 on the IX7s and still have the damn charging system message on my dash. I really don’t know what else to do.
Im just bringing it to the tuner a day early and telling him to do what ever he wants, try and fix it, disable the damn code I really don’t care at this point lol
Im just bringing it to the tuner a day early and telling him to do what ever he wants, try and fix it, disable the damn code I really don’t care at this point lol