which spark plugs, when to change?
Thread Starter
Drifting
Joined: Oct 2009
Posts: 1,537
Likes: 165
From: Lombard, IL (Chicago suburbs)
which spark plugs, when to change?
My 08 has 55k miles and as far as I know the plugs in the car are original. The car runs fine but is used on track regularly and i'm wondering if the next time I spend a weekend doing maintenance i shouldn't add plugs to the list. I changed the plug wires about 8 years ago when one failed so i would probably swap those over as well.
Safety Car
Joined: Sep 2005
Posts: 4,226
Likes: 643
From: Orange County Ca
About a year ago, I pulled a plug on a 60k mile '09 and the little tip of the center electrode was eroded/gone. .080" gap. This was the same for 5 of 8.
The funny thing is that other than a slightly rough idle, the car ran fine.
New plugs may have helped the idle, but overall, it ran about the same.
Recently, I changed the plugs on a 70k mile '14, and they still looked really nice.
I think both cars had oem original plugs.
On a c6, it's a fairly cheap and easy job, so I'd at least check a couple of the easy to get out ones.
The funny thing is that other than a slightly rough idle, the car ran fine.
New plugs may have helped the idle, but overall, it ran about the same.
Recently, I changed the plugs on a 70k mile '14, and they still looked really nice.
I think both cars had oem original plugs.
On a c6, it's a fairly cheap and easy job, so I'd at least check a couple of the easy to get out ones.
Safety Car
Joined: May 2016
Posts: 4,662
Likes: 1,846
From: Erlanger, Kentucky
I know that the stock iridium plugs are supposed to be good for 100K miles. But spark plugs like oil changes are easy to do and are cheap. I would do 25K miles and change the plugs. At most, I would go 50K miles. And I would go with either stock AC Delco iridium plugs are the equivalent in an NGK plug (I cannot confirm but NGK supposedly make the AC Delco iridium plugs for GM).
Safety Car
Joined: Oct 2007
Posts: 4,222
Likes: 1,077
From: South Florida
Iridium plugs at 500-1000rwhp apps seem to last 50k to 80k at 170hp/liter(4-6L V8) and seem to get 13k to 25k miles at 250hp/liter on some customers cars (RB25, 2jz, etc...) with E85 in roll racing apps
