AC Delco Spark Plugs
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Joined: Aug 2010
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From: Iowa
AC Delco Spark Plugs
Guys I need some help on the correct AC spark plug # for a new to me 2003 convertible with 38 k miles. The owners manual calls for 41-974. Looking at that number the audit trail gets murky and ambiguous in a hurry. 41-110 41-985 41-962. Intended purpose of the car is probably not much more than take my wife of 55 years to the ice cream joints on nice days. I'm not running NKGs. Thanks guys. .
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Joined: Mar 2017
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From: Orlando Florida
41-974 were double platinum, apparently discontinued. Many — and I’m one of them — found several plugs where the ground strap platinum pad was missing in action, leading to huge plug gaps. 41-962 is also double platinum. Pass
41-110 & 41-162 are iridium, with very small diameter center conductors — hard, hard material that lasts very long, and the small diameter produces ignition at lower voltages. The go to plug type for a stock motor.
Interestingly, Summit’s fitment guide does NoT list the 41-110 as suitable for the LS6
41-110 & 41-162 are iridium, with very small diameter center conductors — hard, hard material that lasts very long, and the small diameter produces ignition at lower voltages. The go to plug type for a stock motor.
Interestingly, Summit’s fitment guide does NoT list the 41-110 as suitable for the LS6
Safety Car
Joined: Mar 2017
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From: Orlando Florida
Forgot to ask: why no NGK? Previous bad experience?
Curious because you are also going to need new wires — OEM are well known to come apart on the first plug change.
Go to wires have been GM high performance, 89017270, but many options work just as well, some for very good prices.
Curious because you are also going to need new wires — OEM are well known to come apart on the first plug change.
Go to wires have been GM high performance, 89017270, but many options work just as well, some for very good prices.
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Joined: Nov 2003
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From: Bugs Bunny should'a made a left turn here
just be careful where you get your plugs. i bought some "NGK" plugs from amazon and they were counterfeit fakes...lesson learned.
bought the real NGK plugs from o'reilleys and it resolved all my other car's issues.
bought the real NGK plugs from o'reilleys and it resolved all my other car's issues.
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From: Iowa
Safety Car
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From: Orlando Florida
The Gearwrench magnetic swivel worked on all eight of mine. I may have used an additional extension on seven, do not recall for certain, but the swivel socket worked a treat for very few dollars. I also very much liked the Lisle spark plug boot pliers. Both had been recommended by other forum members.
Heel & Toe
Joined: Jul 2023
Posts: 24
Likes: 4
From: Nashville, TN
JDiv48 -
I used this youtube as a guide:
Double offset Lisle spark plug pliers are a must for the wires: https://www.rockauto.com/en/moreinfo...000744&jsn=773
I started out just grabbing the rubber, but switched to lightly pulling on heat shield grabbing around the outside. Grabbing the heat shield helped pull them out easier (and didn't deform the heat shield).
The video shows how you can remove the brake booster line to get a bit better access to the rear driver's side for installation/removal.
For the plugs, agree with the above a good plug socket is needed, and a lot of extensions/patience. Particularly for installing the wires and making sure they are seated properly.
Hope that helps.
I used this youtube as a guide:
Double offset Lisle spark plug pliers are a must for the wires: https://www.rockauto.com/en/moreinfo...000744&jsn=773
I started out just grabbing the rubber, but switched to lightly pulling on heat shield grabbing around the outside. Grabbing the heat shield helped pull them out easier (and didn't deform the heat shield).
The video shows how you can remove the brake booster line to get a bit better access to the rear driver's side for installation/removal.
For the plugs, agree with the above a good plug socket is needed, and a lot of extensions/patience. Particularly for installing the wires and making sure they are seated properly.
Hope that helps.
Racer
Joined: May 2021
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