What's wrong with this plug?
 

The car is a 2000 SS, LS6 manifold, 150 shot NOS plate, 1000psi, 63nos jet - 38fuel jet, racetronix fuel pump, and NGK TR6 plugs. The car runs on pump gas and has 3 degrees of timing pulled from 3000rpms to redline. what would have caused the cylinder 8 plug to look like this?

http://img.photobucket.com/albums/v6...a/DSC06889.jpg
http://img.photobucket.com/albums/v6...a/DSC06887.jpg
http://img.photobucket.com/albums/v6...a/DSC06892.jpg
As you can see the cylinder 8 plug electrode has some melting going on... cylinders 7 looks great and so do all the other ones :confused:

I can't see the pick cause tis blocked at work but if its melted its from 1 or more of the bellow...

Lean condition ,To much timing for the fuel being used, to hot of a heat range on the plug,

ON our cars the # 8 and 7 tend to be the lean cyl from the way the fuel is distrabuted trew the stock rails so there the ones that melt first.

Id lean to to much timing. most guys use the hard fast rule of 3 deg for a 150 shot well i bet if you pull 6 it makes the same power and will be much safer.

How are you tuning? Timing tricker?

+1

You ran a little lean. Those speckles are melted metal. Also looks like you drove a little on the plug before pulling it, hence the decent color on the porcelain. Your gap looks huge in the pictures, what is it really?

I am using HP Tuners to pull timing. The plugs were installed about a 1000 miles ago and i just measured the gap and it is at .038. I am using the NOS recommended jetting, so you think i should up the fuel jet from 38 to 39? From what i've gathered, most 150shot fuel jets are at 36 and NOS is already starting at a 38.. I think i might have some more timing taken out..how much total timing should i take out? any more ideas? Thanks

I'd pull another 3 degrees, and add some fuel in the tune. To be in the safe side of things, pull a degree for every 25 hp of spray. Conservative, but better that then burning up stuff.

Also, are you running the kit off the rail? If so, have you checked to make sure you're not seeing too much a fuel pressure drop? .038 seems like alot of gap too, I don't ever really hear of anyone running more then .035

Drop that gap to .035 and add a little fuel

on 150 shot i would prob go to .032 for the gap

The heat is WAY down on the threads is what I'm seeing. Take 2 degrees out for sure and run a new set of plugs. I ran very clean pulling 5 degrees on a 150 shot and 8 with a 200 shot so far. This is subtracted from a good N/A tune with aggressive timing(ie: not stock). The heat /timing mark should be at or near the base of the ground strap. Above the top thread for sure. The more violent combustion process needs less timing and will make more power once it's done correctly. Goodluck!

thanks guys. i broke my rear end at the track this past weekend so i will be getting a moser 9" and having my tuner take another 3 degrees out. you think i should up my fuel jet by one or two points? i was thinking about a 40... what do you guys think? my nitrous jet is a 63 and my current fuel jet is 38. i will also measure the pressure drop in the rails with a fuel gauge.

I'd leave the nitrous jetting where it is, add some fuel in the tune, get the n/a a/f to about 11.0 via the tune, pull another 3 degrees of timing, and while you're at it put a #7 plug in it too to be safe. I know alot of people spray on #6's, but it's not gonna hurt the car going to a plug that is too cold, a plug that is too hot, whole different story.