Well since FMC discontinued the SP542 plugs, I thought the SP578 was the correct one, since the number supercedes the SP542. Come to find out that I should running M-12405-35T. Which is basically the plugs for the FORD GT with the EcoBoost motor. From what I was told that the 542s where fouling out.
I'll see how the 578s working for now, then switch over. The 578s are colder than the 534s I was running.
Oh here are the 534s I pulled out, I put new plugs in when I switched tuners. I had some gap growth of .007. Plugs where gapped at .026. I had the same growth when running Livernois tunes.
First pic is cylinders 1, 2, 3. Second is cylinders 4, 5, 6.
Yes I was told I didn't drive my car very angrily. Haha
https://performanceparts.ford.com/part/M-12405-35T
Any update on a verdict on these plugs? I am switching tuners to AJP. So I figure since I am also due I will change ALL fluids and replace plugs.
Also was or did the MSD coils make any improvements?
Quote from: Dxlnt1 on August 19, 2020, 10:50:44 AM
Any update on a verdict on these plugs? I am switching tuners to AJP. So I figure since I am also due I will change ALL fluids and replace plugs.
Also was or did the MSD coils make any improvements?
I swapped them in, and for some reason I cannot explain lost a bunch of spark (3-4 points) until i reset the KAM/ECU. Now that the inexplicable weirdness is solved they have been functionally the same for 60 days.
I plan on pulling the front 3 plugs after my road trip and will report on fouling, but i suspect fords got this right on the money with the new tip shape.. just hope the don't get to hot at the tip and crack/break the ceramic.
Quote from: TopherSho on August 19, 2020, 11:41:34 AM
Quote from: Dxlnt1 on August 19, 2020, 10:50:44 AM
Any update on a verdict on these plugs? I am switching tuners to AJP. So I figure since I am also due I will change ALL fluids and replace plugs.
Also was or did the MSD coils make any improvements?
I swapped them in, and for some reason I cannot explain lost a bunch of spark (3-4 points) until i reset the KAM/ECU. Now that the inexplicable weirdness is solved they have been functionally the same for 60 days.
I plan on pulling the front 3 plugs after my road trip and will report on fouling, but i suspect fords got this right on the money with the new tip shape.. just hope the don't get to hot at the tip and crack/break the ceramic.
Sounds good. I ordered a set for $5 I think from Summit. Will install and load new new tune/tuner. Ironically, one of the thing AJP (Brad) sent me was to reset the KAM/ECU lol.
Did you install the MSD coils?
I did indeed. I think it is why my last set of plugs lasted longer, hotter tip.