Spark plug options
Thread Starter
Pro
Joined: Aug 2012
Posts: 657
Likes: 192
From: Memphis Tennessee
Spark plug options
I'm looking at changing out my plugs. I've read some people going with Brisk and some people going with NGK. I called NGK and they said they only have the LTR7IX-11 and I was wanting one step colder than stock but the guy I talked to said he isn't sure what the stock heat range is and said the LTR7 is the only one he has anyway. I was looking at the Brisk RR14 or 12 as well. Can anyone give me a part number for a plug for either Brisk or NGK that's one step colder than stock?
Thanks
Thanks
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
All small block plugs from the factory are DENSO.
C7 ZR1's use one step colder plugs than Zo6's. Higher number = colder
LT1 = DENSO #16 heat range, 1.02mm gap
LT4 = DENSO #20 heat range, 0.8mm gap
LT5 = DENSO #22 heat range, 0.8mm gap
C7 ZR1's use one step colder plugs than Zo6's. Higher number = colder
LT1 = DENSO #16 heat range, 1.02mm gap
LT4 = DENSO #20 heat range, 0.8mm gap
LT5 = DENSO #22 heat range, 0.8mm gap
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
You mean Delco A/C? I see Delco coming out of mine?
Last edited by 3 Z06ZR1; Nov 16, 2018 at 01:19 AM.
Le Mans Master
Joined: Aug 2001
Posts: 6,071
Likes: 297
From: Savannah GA
Cruise-In IV Veteran
Running one step colder Brisk Silver from Katech for my Procharged Port Inection build @18psi. So far not a single complaint working great car feels absolutely ridiculous fast. Will have to change more often but that’s ok with me.
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
Same plug, they are manufactured by DENSO but have an AC Delco logo. If you close at the housing you will see they say "assembled in the USA with Japanese and USA parts" --> DENSO = Japanese Company
GM forces suppliers to put AC Delco logos on parts so you will purchase replacements from GM directly. That way they can mark them up and make boat loads of $$ on replacement parts.
GM forces suppliers to put AC Delco logos on parts so you will purchase replacements from GM directly. That way they can mark them up and make boat loads of $$ on replacement parts.
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Melting Slicks
Joined: Oct 2007
Posts: 2,398
Likes: 858
For the record the NGK LTR7IX-11 is one heat range colder than the stock ACDELCO 41128.
It also comes gaped at .44 rather than the stock .30.
Not sure if the Denso's are exactly the same as what they provide for AC Delco.
The Denso's I have seen have a ridged insulator and the AC Delco's have a smooth insulator.
https://www.rockauto.com/en/catalog/...park+plug,7212
It also comes gaped at .44 rather than the stock .30.
Not sure if the Denso's are exactly the same as what they provide for AC Delco.
The Denso's I have seen have a ridged insulator and the AC Delco's have a smooth insulator.
https://www.rockauto.com/en/catalog/...park+plug,7212
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
For the record the NGK LTR7IX-11 is one heat range colder than the stock ACDELCO 41128.
It also comes gaped at .44 rather than the stock .30.
Not sure if the Denso's are exactly the same as what they provide for AC Delco.
The Denso's I have seen have a ridged insulator and the AC Delco's have a smooth insulator.
https://www.rockauto.com/en/catalog/...park+plug,7212
It also comes gaped at .44 rather than the stock .30.
Not sure if the Denso's are exactly the same as what they provide for AC Delco.
The Denso's I have seen have a ridged insulator and the AC Delco's have a smooth insulator.
https://www.rockauto.com/en/catalog/...park+plug,7212
I have seen that same A/C plug for a long time they use it in other models too using different gaps .. it is really good plug for about 75-80k at 100k it is a little too worn for me.
Last edited by 3 Z06ZR1; Nov 16, 2018 at 05:34 PM.
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
For the record the NGK LTR7IX-11 is one heat range colder than the stock ACDELCO 41128.
It also comes gaped at .44 rather than the stock .30.
Not sure if the Denso's are exactly the same as what they provide for AC Delco.
The Denso's I have seen have a ridged insulator and the AC Delco's have a smooth insulator.
https://www.rockauto.com/en/catalog/...park+plug,7212
It also comes gaped at .44 rather than the stock .30.
Not sure if the Denso's are exactly the same as what they provide for AC Delco.
The Denso's I have seen have a ridged insulator and the AC Delco's have a smooth insulator.
https://www.rockauto.com/en/catalog/...park+plug,7212
Race Director
Joined: Nov 2012
Posts: 11,048
Likes: 3,390
I'm looking at changing out my plugs. I've read some people going with Brisk and some people going with NGK. I called NGK and they said they only have the LTR7IX-11 and I was wanting one step colder than stock but the guy I talked to said he isn't sure what the stock heat range is and said the LTR7 is the only one he has anyway. I was looking at the Brisk RR14 or 12 as well. Can anyone give me a part number for a plug for either Brisk or NGK that's one step colder than stock?
Thanks
Thanks
Thread Starter
Pro
Joined: Aug 2012
Posts: 657
Likes: 192
From: Memphis Tennessee
I've gotten conflicting responses on asking if the LTR7IX-11 is one step colder or stock heat range. Vengeance says it's stock, NGK says it's stock. But two other people I've spoken to say it's one step colder, and you're now the third that says it's one step colder.
Racer
Joined: Nov 2017
Posts: 473
Likes: 89
From: Yorba Linda CA
I'm running RR10S with a 9% Innovators West pulley and a tune. Went two steps colder due to higher boost pressure (at my tuner's direction). The RR's from Brisk are their Racing Silver model and are all non-projected.
Melting Slicks
Joined: Oct 2007
Posts: 2,398
Likes: 858
But here is how I came to my position.
If in fact Denso makes AC Delco's plugs and the heat range numbers for the two are the same we can deduce the following.
1. The OEM ACDELCO 41128 has a heat range of 20 according to info posted on Rock Auto for the plug. https://www.rockauto.com/en/moreinfo.php?pk=6500556&cc=3315156&jsn=4 21
So
2. If we take the Denso heat range of 20 and plug into this cross reference we will see this equates to a heat range of 6 for NGK plugs. https://www.pacificcustoms.com/boschwr8dc.html
Therefore a NGK plug with a heat range of 7 is 1 range colder than the OEM AC Delco 41128.
But not to go on just one example. If you cross the BOSCH 96313 which is the recommended Bosch replacement for the OEM AC Delco 41128 you will see that it's heat range of 7 equates to Denso's 20 and NGKs 6. This all but confirms the NGK LTR7IX-11 (heat range of 7) is 1 range cooler than the OEM plug.
https://www.rockauto.com/en/moreinfo.php?pk=8103676&cc=3315156&jsn=4 23&jsn=423
Of course I am assuming this cross reference chart is correct and NGK or Denso haven't changed their heat range classification strategy since this info was posted.
Other than this all we have is hearsay.
Happy Thanksgiving Folks!!!
Last edited by dar02081961; Nov 23, 2018 at 05:01 AM.
1st Gear
Joined: Dec 2019
Posts: 1
Likes: 0
Ok I understand exactly how you feel. Been through this and still am not 100% sure.
But here is how I came to my position.
If in fact Denso makes AC Delco's plugs and the heat range numbers for the two are the same we can deduce the following.
1. The OEM ACDELCO 41128 has a heat range of 20 according to info posted on Rock Auto for the plug. https://www.rockauto.com/en/moreinfo.php?pk=6500556&cc=3315156&jsn=4 21
So
2. If we take the Denso heat range of 20 and plug into this cross reference we will see this equates to a heat range of 6 for NGK plugs. https://www.pacificcustoms.com/boschwr8dc.html
Therefore a NGK plug with a heat range of 7 is 1 range colder than the OEM AC Delco 41128.
But not to go on just one example. If you cross the BOSCH 96313 which is the recommended Bosch replacement for the OEM AC Delco 41128 you will see that it's heat range of 7 equates to Denso's 20 and NGKs 6. This all but confirms the NGK LTR7IX-11 (heat range of 7) is 1 range cooler than the OEM plug.
https://www.rockauto.com/en/moreinfo.php?pk=8103676&cc=3315156&jsn=4 23&jsn=423
Of course I am assuming this cross reference chart is correct and NGK or Denso haven't changed their heat range classification strategy since this info was posted.
Other than this all we have is hearsay.
Happy Thanksgiving Folks!!!
But here is how I came to my position.
If in fact Denso makes AC Delco's plugs and the heat range numbers for the two are the same we can deduce the following.
1. The OEM ACDELCO 41128 has a heat range of 20 according to info posted on Rock Auto for the plug. https://www.rockauto.com/en/moreinfo.php?pk=6500556&cc=3315156&jsn=4 21
So
2. If we take the Denso heat range of 20 and plug into this cross reference we will see this equates to a heat range of 6 for NGK plugs. https://www.pacificcustoms.com/boschwr8dc.html
Therefore a NGK plug with a heat range of 7 is 1 range colder than the OEM AC Delco 41128.
But not to go on just one example. If you cross the BOSCH 96313 which is the recommended Bosch replacement for the OEM AC Delco 41128 you will see that it's heat range of 7 equates to Denso's 20 and NGKs 6. This all but confirms the NGK LTR7IX-11 (heat range of 7) is 1 range cooler than the OEM plug.
https://www.rockauto.com/en/moreinfo.php?pk=8103676&cc=3315156&jsn=4 23&jsn=423
Of course I am assuming this cross reference chart is correct and NGK or Denso haven't changed their heat range classification strategy since this info was posted.
Other than this all we have is hearsay.
Happy Thanksgiving Folks!!!
