Have a look at these plugs

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11.2

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What do the gurus think. These were pulled after a some good wot but unfortunately about 15 minutes of cruise from light to light to get to my house.
I've been having some high rpm miss issues so I thought I would start with a plug change, I'm running fast efi and the miss goes away if I lean out wot
Sorry, I should have taken some close ups.
 

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Just a few observations and comments.
1. When lead was taken out of gas, the reading of plugs is not readily possible.
2. Your pictures are horrible. Looking down in the plug provides useful information.
3. The plugs look dirty on the insulators, so they have been in awhile. Dirty insulators leads to loss of spark energy.
4. At least 3 have fouling, the gaps appear tight on those. What is your gap setting, they look tight?
5. You may have weak ignition, vacuum leaks and other mechanical issues resulting in imbalance . I am saying that because they differ. Is it a TBI system?
6. Tuning EFI without AFR is rediculous.
 
Currently gaps are at .035, they were at , .045 and it was suggested to try closing the gap to see if it helped my miss. No surprise there was no change. I'm not sure where you got the idea that I don't have afr. I'm using the fast throttle body style.
The reason I posted those pics is cause there is a difference that I am concerned with but I don't know how to tell if a plug is fouling. Wich ones are you referring to?
Once again I apologize about the pics, I could take some close ups if it would help
 
Lower right and left, upper left and one below have fouled at some time.

Fouled plugs may not always clean themselves. The fouling destroys the insulating properties, and results in weak or no spark. You might try changing plugs, check the plug cable resistances, check other ignition components. Verify timing. Check spark intensity with adjustable visible spark test on each cylinder.

I find that on a well tuned engine the plugs remain clean, regardless of how it is driven.

AFR can give wrong readings if the sensor is polluted by extremely rich mixtures.

Tuning an engine under load at wide open throttle involves setting table values at each RPM cell for maximum MAP. Not sure how all that is done on Fast.

Miss fire means significant problems in ignition or fuel mixture. I find engines have significant toleration to both timing and fuel mixture offsets, and still run not too bad from drivers seat. The missing means something is off, timing several degrees or more, fuel 10% or more off.
 
I ran last season with wot set at 12.8. This year I started to miss with that same setting, I tried richening to 12.5 and it got worse, went to 13.0 and it went away but since I ran previously at 12.8 fine I figured it's something else.
 
It takes a good ignition to fire rich or lean mixtures. Following what works is key. You may not have the detail you think, O2 sensor location reading mixed cylinders at one collector .... ? WBO2 is cheap, but may not be accurate to 0.2.

I think you have fuel/air distribution problem among cylinders, and weak ignition. But saying that is a big guess.... I am reading plugs from poor picture with unknown prior use, then reading between the lines on the miss. Take what ever I say as a grain of salt.
 
I changed plugs and instantly had better response and miss is gone but it was a short test drive. I pulled a couple including the one that is leaner than the rest and it still seems a tad leaner but I'm terrible at reading plugs especially when they've been run for short period. I'm gonna get some miles on and pull plugs again.
Thanks for your help
 
Check for vacuum leak on that cylinder. If there is a vacuum port with a leak on that runner might be an easy thing to look for.
 
Hey 11.2, visit "4 seconds flat.com" and click on the section about spark plug reading. This guy is good and all about Mopar ignition and timing. -Sean
 
Edelbrock Performer RPM 7176 but gonna be switching to an air gap intake in hopes of keeping the fuel a little cooler.
 
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