The general grunginess of them suggests they might be original; what's your mileage? I think there was something on here recently about the 7.4 not running well with a very large plug gap. The 41- number usually denotes iridium plugs which are supposed to last longer. Those look donesies to me though!
179k miles. The plug wires have been replaced, at least I'm assuming that, since the UMP set I bought was identical to what was on there, so it's probably they weren't, now I think about it. According to the parts number, they are platinums, which would be what was in there from OE.... That's what I put in there, Denso platinums pre-gapped at .040:
DENSO 4511
Less bad = moar better. Those studs are a pain in the ass to fish out. I only had one broken.
It was in there good and deep. Of your timing map is stock I wouldn't expect to see any KR. You should be adding some timing in there, be sure to bring it in sooner too.
Did you just drill the studs or do you have some other magic?
My timing map is a direct copy-pasta from an 8.1, the black box is based on different parameters so I couldn't really use it, comparing them they are just very different....
I have not seen any knock to speak of, actually was trying to find reading on how best to safely add timing.... any pointers on that end I'm open.
Just add a couple degrees at a time and test?
