Spark Plug Issue SC SRT10

[SCSRT10]

Hi...been lurking for a long time...but never posted...till now...

Have an issue with plugs getting damaged...possible detonation.

Running the NGKZFR6F-11 but as seen in the photo they are being affected by possible detonation...

Im using the factory gap of .044...but some here are using anywhere from .028 to .033 My main question is if Im using .044 with octane 91 could detonation be a reasonable explaination for the plug damage. Im having the piston heads checked today...just scoping them through the plug hole...dont want to start taking the engine apart if I dont have too! Anyone here have similar issues? Running a Paxton Novi 2000.

Derrick

 

[VENOMOUS1 RACING]

Doesn't so much look like detonation as much as it does PTV issues. My guess is it had been overrevved a few times, or the heads were milled some without adding shorter pushrods to the mix? Are all plugs like this? Could be floating valves and springs are fatigued as well? Doesn't look crystalized enough to be detonation but running only 91 that is possible.

How long have you run this combo? I'd spend a couple dollars on a new RC12 Champion plug and compare lengths and protrusion into the chamber to your NGKs. They may be a bit too long. I'd stay around the .040-.044 on the plugs as well.

 

[Slitherbeast]

Hard to see from my iPhone but looks like they are getting to damn hot! They are black from running them to long after a hot run that they are fouled! Get new ones and make a run then immediately shut it down and pill the plugs. You will get better readings ! Are they all that way?

 

[SCSRT10]

Only 1 and 4 were like this the first time...same thing happened 2 months later with three different plugs...same type of plug though. Again only octane 91 being used. Will know more in the next couple of days...I posted earlier on here today with more info but didnt see the post come up on here so this one is sort of a duplicate post...:dontknow:

 

[VENOMOUS1 RACING]

Only 1 and 4 were like this the first time...same thing happened 2 months later with three different plugs...same type of plug though. Again only octane 91 being used. Will know more in the next couple of days...I posted earlier on here today with more info but didnt see the post come up on here so this one is sort of a duplicate post...:dontknow:

I'm still leaning towards piston to valve contact. Either the plug is too long or the valve springs aren't holding anymore.

If I'm not mistaken it could also be pushrods installed in the wrong position? I think there are 2 different sizes, maybe?:dontknow:

 

[SCSRT10]

I bought this truck used with the SC intalled with 31k miles on it...put 15k on more on her with no problems...the problems started when I changed out the plugs that were in her...cant remember what they were...I installed the NGKZFR6F-11 as the Paxton site recommends...after about 2000k the first couple of plugs went down...changed them out for the same ones and its happened again after only 500 miles...this time 3 of them went down. Im thinking that the spark plugs are the cause...hoping really lol. If there is no damage to any of the pistons after the scope is done I will use a cold Champion...maybe thats what was in her to begin with.