heat range 8










Spots are tannish and perhaps a little grayish in color. Plugs have been in the car for 5000 miles approx. Car runs good, 8psi, 8.5:1 compression. Let me know what you think.

 

did u pull those after shutting down in the middle of a full power pull? if yes, i would say try taking out some timing and checking the plugs again.

 

last pic looks like a bit of detonation to me...

 

No, these plugs were pulled during a cam swap. They weren't pulled after a pull. I was just curious if they were evidence that the car was detonating. Engine is 8.5:1 with a GT3076r. Timing is around 16* at peak torque, climbing to 21* at 7500rpm.

Don't want the engine to get hurt, but I thought the tune was ultra safe for the pump gas, considering this was 8psi map.

 

even at peak torque, 16 degrees seems low for 8 psi and 8.5:1 compression. 21 degrees up top sounds ballpark. what octane pump gas?

 

Not much you can tell from an old set of plugs that you pull during a cam swap.

 

put new plugs in and do a wot pull, or two, and shut down pull plugs and take more pics. Hard to read crusty *** plugs from awhile ago.

 

They do show signs of detonation but it's bet to do a power pull with a fresh set and shut it down and pull plugs then Take pics

 

I am on 91 pump gas. And I know that the plugs should have been pulled after a pull to check for detonation, but I was curious why the deposits were there. Not sure if it was signs of past detonation or not, but I figured 8.5:1 compression should be rather safe. Engine is runnin 13psi now. Going to dyno and putting new plugs in.