Correct spark plugs?
Thread Starter
Intermediate
Joined: Mar 2019
Posts: 40
Likes: 5
Correct spark plugs?
So I've been hearing a bunch of different things and honestly starting to get confused. For Starters My car is 2014 z51 with basic mods: AFE intake, Ported Throttle Body/Intake Manifold, TSP 1-7/8" long tube headers and catless x-pipe, DSX flex fuel sensor and Tune.
So long story short, I did a couple of pulls on the street ( nothing to crazy) when I let off the pull and was driving normal the vehicle started to backfire after about 3 minutes the car check engine light came on and started flashing. Found out cylinder 3 was dead so switched out the spark plug with another stock one, just to confirm it was a spark issue. The spark plug was a good color as well. The vehicle is now running fine, But this leads me to my main question.
Are the stock plugs suffice or do I need to go one step colder on this set up? I've been told by some people the stock spark plugs should be fine and it was just a faulty plug and that the E85 should cool the Chambers and there No need to go one step colder. Others have said go with one step colder and that NGK LTR7IX (6510) is the way to go. But now being Told that 6510 is one step colder for the Z06. I've also been told to use LTR6IX these are the correct one step colder plugs for the LT1.
Any input will help. Thank you in Advance
So long story short, I did a couple of pulls on the street ( nothing to crazy) when I let off the pull and was driving normal the vehicle started to backfire after about 3 minutes the car check engine light came on and started flashing. Found out cylinder 3 was dead so switched out the spark plug with another stock one, just to confirm it was a spark issue. The spark plug was a good color as well. The vehicle is now running fine, But this leads me to my main question.
Are the stock plugs suffice or do I need to go one step colder on this set up? I've been told by some people the stock spark plugs should be fine and it was just a faulty plug and that the E85 should cool the Chambers and there No need to go one step colder. Others have said go with one step colder and that NGK LTR7IX (6510) is the way to go. But now being Told that 6510 is one step colder for the Z06. I've also been told to use LTR6IX these are the correct one step colder plugs for the LT1.
Any input will help. Thank you in Advance
Le Mans Master
Joined: Oct 2014
Posts: 8,673
Likes: 2,728
From: Atlanta GA
If the spark plug was good in color I would not change it for bolt on mods
Plug wires poping off and cracked spark plugs are common issues ...I am willing to bet that it was not a bad plug and it just was the wire .....
Little dielectric grease in the boots stops this common issue ...
Dave
Plug wires poping off and cracked spark plugs are common issues ...I am willing to bet that it was not a bad plug and it just was the wire .....
Little dielectric grease in the boots stops this common issue ...
Dave
Thread Starter
Intermediate
Joined: Mar 2019
Posts: 40
Likes: 5
Dave I appreciate you so much haha Can't always count on you when I cant figure something out. By no means am I mechanic so this plug is fine and just needed? grease I sure do feel silly now if that's the case.
Le Mans Master
Joined: Oct 2014
Posts: 8,673
Likes: 2,728
From: Atlanta GA
The LT and LS engines were notorious for the plug wires popping off at the most inopportune time . My guess is it is because of the expansion and contraction of the air that is trapped between the boot and the plug .
I learned the hard way also when I had one pop off just after I installed my headers on my C6 . Now I use just a touch of dielectric grease inside the boot , this allows the boot to slide on and you can feel the snap when the wire is securely on the plug
Dave
Advanced
Joined: May 2015
Posts: 89
Likes: 12
From: Nebraska
Marquis Gallegos ;
I run the Brisk Silver racing plugs in my ZO6 ( P/N: RR15YS SILVER 1585 gaped @ 0.025") and also use the Granetelli Zero Ohm Plug wires, Running with these added 20 hp on the dyno, that was crazy to see. On top of that the outside pipes no longer are black from running a rich mixture, and now burns all the fuel. No stuttering and misfires, and at full throttle it even sounds meaner according to the guys on the track that know me.
Throw those iridium tipped spark plugs and the OEM wires in the trash. OEM plug wires resistance are anywhere from 3 - 5 K ohm. If you are running your car hard it's a good idea to change or at the very minimum look at them after 10,000 miles.
The next plug I'll put in after the warranty expires will be the Brisk Premium ( P/N: POR15LGS PREMIUM 2145 )
These plugs are for forced induction so unless you have a Procharger on the LT1 you'll need two heat ranges hotter plug and the gap will be a little wider. I don't have the specs for the NA motor but if you find a dealer they will be able to point you in the right direction.
Lyle
I run the Brisk Silver racing plugs in my ZO6 ( P/N: RR15YS SILVER 1585 gaped @ 0.025") and also use the Granetelli Zero Ohm Plug wires, Running with these added 20 hp on the dyno, that was crazy to see. On top of that the outside pipes no longer are black from running a rich mixture, and now burns all the fuel. No stuttering and misfires, and at full throttle it even sounds meaner according to the guys on the track that know me.
Throw those iridium tipped spark plugs and the OEM wires in the trash. OEM plug wires resistance are anywhere from 3 - 5 K ohm. If you are running your car hard it's a good idea to change or at the very minimum look at them after 10,000 miles.
The next plug I'll put in after the warranty expires will be the Brisk Premium ( P/N: POR15LGS PREMIUM 2145 )
These plugs are for forced induction so unless you have a Procharger on the LT1 you'll need two heat ranges hotter plug and the gap will be a little wider. I don't have the specs for the NA motor but if you find a dealer they will be able to point you in the right direction.
Lyle
Last edited by Hershey71; Aug 23, 2019 at 07:44 PM. Reason: added content.
Le Mans Master
Joined: Oct 2014
Posts: 8,673
Likes: 2,728
From: Atlanta GA
Plenty of 11 second NA LT 1 cars , including mine running those crappy Irdium plugs and oem wires ...save your money
Just my opinion but If u picked up 20 HP from a plug change in would be looking for something else wrong ....
Dave
Just my opinion but If u picked up 20 HP from a plug change in would be looking for something else wrong ....
Dave
Advanced
Joined: May 2015
Posts: 89
Likes: 12
From: Nebraska
Dave,
I was a dis-believer too at first. If I hadn't seen it with my own eyes. . That was the only thing that we changed and it was in the same density air . I could understand that if the density air was lower, actually was a little higher but it was still within 50' of the previous run. On a forced induction motor it shouldn't have made a difference. Previously the car had a miss when idling but after changing the plugs and wires that was gone,
I can't explain it, but don't think it was an anomaly.
Lyle
I was a dis-believer too at first. If I hadn't seen it with my own eyes. . That was the only thing that we changed and it was in the same density air . I could understand that if the density air was lower, actually was a little higher but it was still within 50' of the previous run. On a forced induction motor it shouldn't have made a difference. Previously the car had a miss when idling but after changing the plugs and wires that was gone,
I can't explain it, but don't think it was an anomaly.
Lyle
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Advanced
Joined: May 2015
Posts: 89
Likes: 12
From: Nebraska
The Dyno shop had the plugs and I bought the plug wires on line from Jegs.com,The premium plug has 4 ground terminals and a plug like that has been around for years. The speed shop runs the premium plug in his drag car.
Last edited by Hershey71; Aug 25, 2019 at 09:26 PM.
Thread Starter
Intermediate
Joined: Mar 2019
Posts: 40
Likes: 5
I've been skeptical of doing Granetelli Zero Ohm Plug wires. It just really seems like snake oil to me. I heard a mixture of things from different sources and reputable people/shops. I'm not saying they don't work or the horsepower gain isn't there. I just cant fathom gaining 20hp from something like that, But maybe its true.
Pro
Joined: Apr 2018
Posts: 732
Likes: 90
From: Eastern Pa
Ngk plugs
I have a modded 825HP (wheel hp) C7 LT4, The heads are ported, upgraded cam, ported supercharger and blower, and running straight E85. I was told by a shop owner In South Jersey to use NGK plugs because I told my car is breaking up a little bit at full throttle, he want me to bring the car with him for a week or so, so he can retune the car, change plugs & wires. He would not tell me which plugs he uses.... Does anyone have any idea what a good NGK plug would be for my application? Thanks in advance, really appreciate it.
Racer
Joined: Sep 2021
Posts: 321
Likes: 119
From: Illinois
I have a modded 825HP (wheel hp) C7 LT4, The heads are ported, upgraded cam, ported supercharger and blower, and running straight E85. I was told by a shop owner In South Jersey to use NGK plugs because I told my car is breaking up a little bit at full throttle, he want me to bring the car with him for a week or so, so he can retune the car, change plugs & wires. He would not tell me which plugs he uses.... Does anyone have any idea what a good NGK plug would be for my application? Thanks in advance, really appreciate it.
