Colder range spark plugs
01-11-2016, 04:13 PM
#1
Burning Brakes
Thread Starter
Colder range spark plugs
I have an LS2 with a Comp XER 273 cam and I using OEM Iridium plugs (41-110). The NGK TR6 plugs installed with the cam gave me CEL’s so I went back to the OEM plugs (41-110). At WOT, I get about 3 degrees of knock around 5,000 RPM. Since the LS7 plugs are colder (41-104) I’m considering making the change. Any thoughts on the 41-104’s?
01-11-2016, 05:17 PM
#2
Race Director
Member Since: May 2004
Location: Raleigh, NC
Posts: 16,664
Received 1,193 Likes
on
1,052 Posts
St. Jude Donor '15
That's what I run. Can't hurt to try them.
The following users liked this post:
seevi (01-11-2016)
01-13-2016, 06:30 PM
#3
Drifting
I have an LS2 with a Comp XER 273 cam and I using OEM Iridium plugs (41-110). The NGK TR6 plugs installed with the cam gave me CEL’s so I went back to the OEM plugs (41-110). At WOT, I get about 3 degrees of knock around 5,000 RPM. Since the LS7 plugs are colder (41-104) I’m considering making the change. Any thoughts on the 41-104’s?
The following users liked this post:
seevi (01-14-2016)
01-18-2016, 09:46 AM
#4
Drifting
Go for it...Living in CA, I doubt you'll have any issues with carbon fouling if they are a bit cold for your setup.
I'd rather have a cold plug in it than a too hot of one!
I'd rather have a cold plug in it than a too hot of one!
01-18-2016, 10:15 PM
#5
Le Mans Master
Member Since: Aug 2005
Location: CA.
Posts: 5,255
Likes: 0
Received 281 Likes
on
258 Posts
St. Jude Donor '13-'14-'15
Depends a lot on your cars usage---If it is a daily driver occasional sport driven---There is no advantage to going to a colder plug on your application----Colder plugs when not needed will tend to foul out easier that a hotter plug---The TR6 is generally used on race only cars or engines that run consistently above 6000 RPM's or engines with boost or NOS---
As far as the knock retard goes---I don't think the plugs have anything to do with it---It depends on whether the KR is indeed real (you can hear pinging) or false--you can't hear a thing----Often modded engines with cams and especially LT headers will produce false knock--which can be tuned out to not occur and remove timing----Assuming you have the stock compression ratio and are using premium fuel you should not ever hear any detonation unless your tune asks for too much timing----False knock is what I suspect---
again NOT plug related
As far as the knock retard goes---I don't think the plugs have anything to do with it---It depends on whether the KR is indeed real (you can hear pinging) or false--you can't hear a thing----Often modded engines with cams and especially LT headers will produce false knock--which can be tuned out to not occur and remove timing----Assuming you have the stock compression ratio and are using premium fuel you should not ever hear any detonation unless your tune asks for too much timing----False knock is what I suspect---
again NOT plug related
02-13-2016, 03:24 PM
#6
Depends a lot on your cars usage---If it is a daily driver occasional sport driven---There is no advantage to going to a colder plug on your application----Colder plugs when not needed will tend to foul out easier that a hotter plug---The TR6 is generally used on race only cars or engines that run consistently above 6000 RPM's or engines with boost or NOS---
As far as the knock retard goes---I don't think the plugs have anything to do with it---It depends on whether the KR is indeed real (you can hear pinging) or false--you can't hear a thing----Often modded engines with cams and especially LT headers will produce false knock--which can be tuned out to not occur and remove timing----Assuming you have the stock compression ratio and are using premium fuel you should not ever hear any detonation unless your tune asks for too much timing----False knock is what I suspect---
again NOT plug related
As far as the knock retard goes---I don't think the plugs have anything to do with it---It depends on whether the KR is indeed real (you can hear pinging) or false--you can't hear a thing----Often modded engines with cams and especially LT headers will produce false knock--which can be tuned out to not occur and remove timing----Assuming you have the stock compression ratio and are using premium fuel you should not ever hear any detonation unless your tune asks for too much timing----False knock is what I suspect---
again NOT plug related
02-13-2016, 03:48 PM
#7
Race Director
Member Since: May 2004
Location: Raleigh, NC
Posts: 16,664
Received 1,193 Likes
on
1,052 Posts
St. Jude Donor '15
Not really
02-19-2016, 07:31 AM
#8
Drifting
Most times knock cannot be heard unless it's really bad. You'll never hear knock that the PCM only pulls. Few degrees. Serious knock you can hear but usually only to the trained ear. Most people won't know what the sound is. To the OP I would try the ls7 plugs. Not sure how much power you picked up over stock with cam but if it's 75hp or more (roughly) you should use a colder plug. Generally rule is 1 step colder per 100HP increase. Obviously only to a certain extent. But 100 over stock a colder plug will do you better.
The following users liked this post:
seevi (02-20-2016)
02-19-2016, 02:17 PM
#9
Safety Car
Most times knock cannot be heard unless it's really bad. You'll never hear knock that the PCM only pulls. Few degrees. Serious knock you can hear but usually only to the trained ear. Most people won't know what the sound is. To the OP I would try the ls7 plugs. Not sure how much power you picked up over stock with cam but if it's 75hp or more (roughly) you should use a colder plug. Generally rule is 1 step colder per 100HP increase. Obviously only to a certain extent. But 100 over stock a colder plug will do you better.
NGK recommends "one heat range colder for every 75-100hp added.". NGK also recommends to err on the cold side. I would rather change my plugs a little more frequently, than damage the engine from too hot of a plug.
The following users liked this post:
seevi (02-20-2016)
02-21-2016, 07:21 AM
#10
Instructor
My 0.02
Running LS3 with Maggie MP112 @7,5 psi
OEM 41-110 plugs showed 5-6 degrees of knock retard (HPT logging)
OEM 41-104 plugs from LS7 show zero in all range.
Running LS3 with Maggie MP112 @7,5 psi
OEM 41-110 plugs showed 5-6 degrees of knock retard (HPT logging)
OEM 41-104 plugs from LS7 show zero in all range.
02-21-2016, 02:13 PM
#12
Race Director
Member Since: May 2004
Location: Raleigh, NC
Posts: 16,664
Received 1,193 Likes
on
1,052 Posts
St. Jude Donor '15
If you're seeing 5-6* of knock you should be concerned
02-22-2016, 01:06 AM
#13
Instructor
Knock Retard Z06 plugs 41-104
Knock Retard stock LS3 plugs 41-110
Spark Advance Z06 plugs 41-104
Spark Advance stock LS3 plugs 41-110
About octane... They say it is Premium, but in fact I'd say it is around 91 oct that you have in US plus a lot of additives (here in Russia we have different octane measuring method)
Vasiliy
02-22-2016, 08:34 AM
#14
Race Director
Member Since: May 2004
Location: Raleigh, NC
Posts: 16,664
Received 1,193 Likes
on
1,052 Posts
St. Jude Donor '15
I didn't realize you were in Russia!
Well, at least you don't have any knock after 2400 RPM's.
Well, at least you don't have any knock after 2400 RPM's.
02-27-2016, 06:24 PM
#15
Drifting
Hey guys I'm coming into this kind of late but very interested.
Firstly, what is dirtyoilman using to log the timing data? I have a tech 2 but dont think that's it.
Secondly, For higher load pulls (I drive up mountains often) has anyone tried a colder plug than the OEM LS7?
I'm running an eforce with 3 inch pulley on LS7.
Firstly, what is dirtyoilman using to log the timing data? I have a tech 2 but dont think that's it.
Secondly, For higher load pulls (I drive up mountains often) has anyone tried a colder plug than the OEM LS7?
I'm running an eforce with 3 inch pulley on LS7.
02-27-2016, 07:02 PM
#16
Race Director
Member Since: May 2004
Location: Raleigh, NC
Posts: 16,664
Received 1,193 Likes
on
1,052 Posts
St. Jude Donor '15
That is HP Tuners software / interface