Iridium plug gap

[Jon]

I just got some TR7IX plugs for my car. What should an iridium be gapped at for 12-14psi of boost and 750-800rwhp?

[Unreal]

28-30

[ChadC]

also keep an eye out of a faulting charging system, over/under voltage on your battery.

while rare, BUT documented enough times that GM did release a TSB on with the iridium plugs.

the iridium plugs cause a form of "dirty" noise on the CANbus circuit fooling the PCM to command the Alternator to over/under charge the battery.

good luck either way bud

[Unreal]

That was copper plugs doing that. ZR1 plugs are iridium along with new z06 plugs.

[ChadC]

That was copper plugs doing that. ZR1 plugs are iridium along with new z06 plugs.

some copper, some iridium. the c6zr1 uses ACDelco, not NGK. this is a C6 NOT a C7. completely different car.

Ill repeat my point.

by the mere act of changing spark plugs can cause a Charging system error. So enjoy your car Jon, but if you get that error start with the plugs first and not the battery/alt.

[HOXXOH]

That was copper plugs doing that. ZR1 plugs are iridium along with new z06 plugs.

some copper, some iridium. the c6zr1 uses ACDelco, not NGK. this is a C6 NOT a C7. completely different car.

Ill repeat my point.

by the mere act of changing spark plugs can cause a Charging system error. So enjoy your car Jon, but if you get that error start with the plugs first and not the battery/alt.

If I understood the problem correctly, it was an internal gap difference on the center electrode that caused the noise. I agree if the charging system goes nuts to swap plugs first.