SPARK PLUG preferences
Safety Car
Joined: Jan 2006
Posts: 4,598
Likes: 78
From: Miami FL
2020 C6 of the Year Finalist - Unmodified
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16,'17,'18-'19-'20-'21-'22
Oem ftw
Get the iridium AC/Delco spark plugs for your base C6. Other brands have from time-to-time caused electrical issues. GM knew what they were doing for the spark plugs.
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,629
OEM Plugs will last 100K, and the plugs that you want to use in the motor.
Myself, I pull them about every 30K to clean them up/check the gaps, then use antiseaze on the threads to I can spin them back out in another 30K until they are worn out at the 100K mark. If your just pulling/replacing the plugs every 100K, then don't use antiseaze on the threads, since the threads come pre coated when new.
Same goes for OEM spark plug wires as well, hence good for 100K.
The reason for the two, some after market plugs and wires do not have the correct amount of resistance (works as a RF noise suppressor from the spark plugs back up to the coils), which can cause RF noise in the coils that feeds back to the ECM. When the ECM get enough RF noise through it, and since it controls the voltage on the alternator, the Ecm will lower the standard 14.7 volts output of the alternator to lower voltage, and you will get service charging system trouble messages/codes.
Myself, I pull them about every 30K to clean them up/check the gaps, then use antiseaze on the threads to I can spin them back out in another 30K until they are worn out at the 100K mark. If your just pulling/replacing the plugs every 100K, then don't use antiseaze on the threads, since the threads come pre coated when new.
Same goes for OEM spark plug wires as well, hence good for 100K.
The reason for the two, some after market plugs and wires do not have the correct amount of resistance (works as a RF noise suppressor from the spark plugs back up to the coils), which can cause RF noise in the coils that feeds back to the ECM. When the ECM get enough RF noise through it, and since it controls the voltage on the alternator, the Ecm will lower the standard 14.7 volts output of the alternator to lower voltage, and you will get service charging system trouble messages/codes.
Pro
Joined: Nov 2013
Posts: 552
Likes: 58
From: western NC, USA
I had iridium plugs that lasted 50k (electrode was burned off two of them). My tuner, who installed an aftermarket cam/kit) recommended staying with the iridiums since they will last longer than the copper electrode kind.
