View Full Version : Spark Plugs for 2013 Ilmor 6.0

10-16-2013, 12:27 PM
So I have about 100 hours on my 2013 Ilmor 6.0 and while winterizing I am replacing the spark plugs. I went to Napa with the Stock ACDelco 41-110 plugs and they ordered me new ones. When I picked them up this morning they are a different part number, ACDelco 41-962. The guy at Napa said these are the replacement plugs. I am wondering if these are the right plugs to use on this motor? The definitely look different. Anyone here have experience with this?

10-16-2013, 12:31 PM
Any reason why you are changing the plugs? MMS did my 100-hour service and all the plugs were inspected.

10-16-2013, 12:39 PM
On all my old V-drives, I replaced the plugs after ever 100 hours or once a year. The plugs don't look too bad, but I figure on a boat like this, and for how much we use it, $90 for new plugs once a year seems like a worthy investment. When I called MMS they said the same thing, just inspect them. I figure if I have to inspect each one anyways, might as well replace them at this time.

10-16-2013, 12:41 PM
:confused::confused:one is the iridium the other is platinum - wonder why this is second post that calls out napa for changing type of plug...

10-16-2013, 02:04 PM
So I spoke with my service department and they said that the correct plugs are the ACDelco 41-985. I did some google searches and a few years back, these were replaced by the part number 41-110. But they are in fact the exact same plug.

I also sent an email to Ilmor, but didn't expect to hear back for a while. The responded right away with the detailed information below. Very impressed with the service form Ilmor for that.

Our part Num# Mv8v-1192 is the same spark plug# as AC Delco 41-110. That's is the spark plug you need. 41-962 I cannot answer if it is alternate plug. I would not use them, especially if they look different.

Thank You!

So I'm taking these plugs back to Napa and will just have to get them elsewhere I guess. I'm glad I didn't just "trust" the Napa guy.

10-16-2013, 03:07 PM
Good thing you investigated first Levi. Scary that they would just elect a seemingly random plug to sell to you. Was that here in town?

10-16-2013, 04:31 PM
Sure was. I even went back in and showed him the two plugs and how they looked different, and he said "ya, they are fine". No biggie though, I found them online pretty cheap if he can't get them.

10-16-2013, 04:40 PM
Those guys seem a little sketchy over there sometimes...

10-16-2013, 08:30 PM
Eash - ya use that part you'll be fine.. here's your sign...

10-16-2013, 08:49 PM
$90 for plugs? I know you guys use monopoly money up there but still that seems high!

10-16-2013, 09:05 PM
I switched to Iridiums (AC Delco 41-993) in our 09. It was good switch, she seems to run a little better.

10-16-2013, 10:29 PM
My dealer wanted over $200 for the 8 plugs, but didn't have stock so I went to a local auto parts store and found the proper 41-110's. Cheap too.

10-16-2013, 10:29 PM
And I wanted Togo with exactly what Ilmor recommends.

10-17-2013, 04:20 AM
Wondering if you'd be better to wait until spring to change them. Large variations in temperatures (winter) and electronics. Likely little impact, might be a false worry.

10-17-2013, 07:47 AM
The "normal" plug for the whole GM LSx engine family (which includes the 6.0L) cross references with an NGK TR5 (copper). There are platinum and iridium variants also available at just about any auto parts store.

FWIW, NGK heat ranges get colder with increasing numbers, so a TR6 is the next colder plug for this engine that we would use on a supercharged application. Since this is a marine engine that intentionally runs cooler, I would not go any colder on the plug for fear of fouling, so you're best to stick with something like a TR5 or TR55ix (iridium, pre-gapped).