Factory Plugs
Thread Starter
Intermediate
Joined: Aug 2011
Posts: 35
Likes: 0
From: Ann Arbor MI
Factory Plugs
Hi all.
I am performing the 100000 mile maintenance on my 07 Z51 Convertible and I noticed that the original plugs, which were actually Iridium, seem to no longer be available under the original part number.
In Rock Auto, I ordered the AC Delco ones that were supposed to be OEM but they turn out to be double platinum.
Any issue using these? Or is there a new AC Delco Iridium I should use?
I am performing the 100000 mile maintenance on my 07 Z51 Convertible and I noticed that the original plugs, which were actually Iridium, seem to no longer be available under the original part number.
In Rock Auto, I ordered the AC Delco ones that were supposed to be OEM but they turn out to be double platinum.
Any issue using these? Or is there a new AC Delco Iridium I should use?
Burning Brakes
Joined: Feb 2021
Posts: 771
Likes: 399
2022 C6 of the Year Finalist - Unmodified
These are the plugs I replaced my stock delcos with in my 2011
Not a problem with drivability...even after 3-4 pulls on the dyno....
ACDelco GM Original Equipment 41-110 Iridium Spark Plug
Not a problem with drivability...even after 3-4 pulls on the dyno....
Drifting
Joined: Apr 2016
Posts: 1,286
Likes: 611
From: DFW Texas
Send the double platinum plugs back. They were never OEM for the C6. The original OEM was ACDelco 41-110, but if you go to the ACDelco website, they are no longer recommended for the Corvette. The ACDelco recommended replacement is now ACDelco Iridium Spark Plug 41-162.
GD
GD
Last edited by gdmoore01; Sep 21, 2021 at 10:22 PM.
Drifting
Joined: Jul 2011
Posts: 1,825
Likes: 443
From: Boca Raton Florida
Originally Posted by blownbayou
These are the plugs I replaced my stock delcos with in my 2011
Not a problem with drivability...even after 3-4 pulls on the dyno....
ACDelco GM Original Equipment 41-110 Iridium Spark Plug
Not a problem with drivability...even after 3-4 pulls on the dyno....
Burning Brakes
Joined: Dec 2011
Posts: 876
Likes: 116
From: HOMESTEAD FL
I use the NGK TR5ix (.040 pre-gap) (Iridium IX) plugs on my 2011 GS.
Quick story: So @15,000 miles the car was on its original spark plugs and was really running very poorly. At the time It was showing a noticeable loss of power and a very rough idle. I asked about the spark plugs and the tech at the dealership assured me that GM uses "100,000 mile plugs" and they could not possibly be the issue since my car only had 15,000 miles at the time... and he didn't even bother to remove a single plug.
After letting the dealership tinker with it, I got it home, I first swapped in a set of MSD wires... that didn't change a thing so I pulled the first plug and the center electrode was all but gone and the side electrode was nearly half gone. The rest of the plugs showed a very similar fate. To this day I still cant believe the dealerships tech didnt even remove a single plug!
I installed the NGK TR5ix plugs I have put over 30,000 miles on the NGK TR5ix plugs checking them about every 5,000 miles and they look just as good as the day I installed them.
So in my opinion, the factory plugs are complete CRAP! Do NOT install a factory replacement plug! I am a fan of the NGK TR5ix plugs...
To be fair, I drive WOT 1st, 2nd, 3rd everywhere I go... so my plugs get abused... the TR5ix plugs can survive my driving and so far lasting over 30,000 WOT miles (and going) ... so they get my vote!
SPEED SAFE, NICK
Quick story: So @15,000 miles the car was on its original spark plugs and was really running very poorly. At the time It was showing a noticeable loss of power and a very rough idle. I asked about the spark plugs and the tech at the dealership assured me that GM uses "100,000 mile plugs" and they could not possibly be the issue since my car only had 15,000 miles at the time... and he didn't even bother to remove a single plug.
After letting the dealership tinker with it, I got it home, I first swapped in a set of MSD wires... that didn't change a thing so I pulled the first plug and the center electrode was all but gone and the side electrode was nearly half gone. The rest of the plugs showed a very similar fate. To this day I still cant believe the dealerships tech didnt even remove a single plug!
I installed the NGK TR5ix plugs I have put over 30,000 miles on the NGK TR5ix plugs checking them about every 5,000 miles and they look just as good as the day I installed them.
So in my opinion, the factory plugs are complete CRAP! Do NOT install a factory replacement plug! I am a fan of the NGK TR5ix plugs...
To be fair, I drive WOT 1st, 2nd, 3rd everywhere I go... so my plugs get abused... the TR5ix plugs can survive my driving and so far lasting over 30,000 WOT miles (and going) ... so they get my vote!
SPEED SAFE, NICK
Last edited by AIR_RAM; Sep 21, 2021 at 10:26 PM.
Race Director
Joined: Mar 2011
Posts: 13,262
Likes: 3,151
From: SW Florida
2021 C6 of the Year Finalist - Modified
Burning Brakes
Joined: Feb 2021
Posts: 771
Likes: 399
2022 C6 of the Year Finalist - Unmodified
Burning Brakes
Joined: Dec 2011
Posts: 876
Likes: 116
From: HOMESTEAD FL
LOL... Nope. over 30,000 street miles. Most people only know their Corvettes are capable cars because people like me tell them they are.
Your Corvette is a very capable car!
Ohh yeah, a good radar detector and knowing how to use it comes in handy. That's saved me from being "observed" more than a few times.
All joking aside, the TR5 IX plugs will outlast the recommended factory plugs. As far as performance... I dont believe properly gapped spark plugs of any brand can make a measurable difference between each other unless they have eroded... get the ones that last the longest... more expensive up front but much cheaper in the long run.
SPEED SAFE, AIR RAM
Your Corvette is a very capable car!
Ohh yeah, a good radar detector and knowing how to use it comes in handy. That's saved me from being "observed" more than a few times.
All joking aside, the TR5 IX plugs will outlast the recommended factory plugs. As far as performance... I dont believe properly gapped spark plugs of any brand can make a measurable difference between each other unless they have eroded... get the ones that last the longest... more expensive up front but much cheaper in the long run.
SPEED SAFE, AIR RAM
Last edited by AIR_RAM; Sep 22, 2021 at 08:27 AM.
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