AC Delco Wires + Professional Iridium Plugs:

[outrun]

Suggested Service Interval?

Plugs are stamped "NGK" and no misfires are detected. Plugs are warrantied to 100,000. However premptive maintence always works better than being kicked when you least expect it. The reason I ask is that there have been reports of efficiency robbing electrode degradation well before this mileage.

I may stay with the professionals if I can ... the Iridium IXs appear very expensive from my price shops so far. OEM Plugs were Professional Platinums which I also had great experiance with.

Thanks!

 

[Jason2007]

Id say they should be good for 65-75k easy.

 

[Herz]

I replaced my acdelco 100k plugs at 110 and the wires, and plugs were still in good condition.

 

[Ibrahim]

I hanged on to mine for 65K Miles on couple of my cars and it was an OVERKILL...i guess it also comes down to how one drives the car, a good time period to change NGK Iridium's in my opinion would be 50-55K Miles!

 

[UNC038]

I changed my first set (plat.) in my blown GTP motor at about 80k with one heat range colder (also plat.) they were in very good condition but gapped a little wide for the spec.

At about 80k later I decide to check the condition of my replacement plugs and fubared a wire without knowing it, the plugs were fine but since I needed to change a wire or two I decide might as well do the plugs while my hands are dirty and bought iridium plugs. So far these have been in for about 35k and runs smooth.

The first two sets of wires were AC Delco with the last being Duralast FWIW.

 

[johnd]

I replaced wires at 60K and it did make a difference-the under hood heat in a Camaro, even without headers, is brutal. Plugs (platinum tip)looked like the day they went in but I replaced them anyway. Right after that, I developed a miss when one of the platinum tips came off of a new plug. I fixed it by putting one of the old ones back in. Now I have 7 plugs with 30K on them and one with 90K-and the engine runs just fine.

 

[GMBoy]

As for wires, I've always replaced my OEM wires with a good set of MSD wires. I went thru 2 sets of AC DELCO wires (the original and a replacement set) on my LT1 Corvette before finally going with MSD's and they've so far outlasted the Delcos. I think the MSD's just handle the heat better and were a tiny bit thicker too - yet still fit in the stock wire holders. I also use them on my Buick GN. I used Acel wires at one point, but was not really impressed.