Spark plug after 75 shot popping out exhaust.
08-01-2005, 10:09 AM
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Spark plug after 75 shot popping out exhaust. posting this in a new thread since no one responded to the new question on my old thread. here of pics of the plugs after a run. pics arent that good but get an idea. porcelin looks good and clean and white, the heat range looked good, only thing i see is the black soot on the base ring? probably just running rich? or what causes that? pics are attached.
08-01-2005, 10:24 AM
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Kind of hard to see the timing mark, but it appears to be well beyond the curve of the grounding strap (looks below the end of the porcelain), indicating too much timing. The soot is from rich yes, could be jetting, or PE, which can help you "pop". Hope this helps.
What plugs are these?
Whats the gap at, looks rather wide?
What plugs are these?
Whats the gap at, looks rather wide?
08-01-2005, 10:53 AM
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sorry for the camera phone pics, its all i had at the time. i highlighted the heat range on the ground strap to help. these are NGK tr-6's set at .038 gap. just a tiny bit wider than what they were set at the factory (.035).
08-01-2005, 01:25 PM
#4
Now when you say popping, do you mean all the time now, or just when stopping run? At the end of a run when snapping throttle closed and decelerating you often hear popping (unburned fuel in exhaust). You can stop this by letting off more progressively rather than snapping throttle shut. Your gap should be fine for a 75 hit, imo. I will leave the reading of the plugs to Cat, as he has this aspect down.
Robert
Robert
08-01-2005, 03:27 PM
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Originally Posted by hourang
sorry for the camera phone pics, its all i had at the time. i highlighted the heat range on the ground strap to help. these are NGK tr-6's set at .038 gap. just a tiny bit wider than what they were set at the factory (.035).
Not sure from the pic, but think if that is your timing mark your timing is off, leading to popping as well, as wrong jetting. Here is what I am looking at as your timing mark, please verify the line within the box. It looks like the GS changes color right there. Also of note, you took these plugs out after you returned to the pit/or drove a bit post WOT N20 Run, as is evident by the washing of the coloring, correct me if I am wrong. The proper way to get a clean reading is run, coast to the turn off, shut down, pull plug, replace with new plug, return to pit area, read and adjust as necessary. PITA yes, but leaves no room for washing. Also, what plugs are you pulling? I recommend you pull from the drivers side on a wet kit, specifically #7. On a wet kit, if there is a fuel issue/distribution problem this will be the tell tale, fuel exits the drvrs side rail, leaving it leaner than even bank, and 7 is rearward so it the one that will bust the ring lands off.
What jetting and nozzle are you using?
Where is it located at?
Pics of that please, phone cam is adequate.
08-01-2005, 03:41 PM
#7
Reading the NOS trouble shooting guide:
High-rpm misfire when system is activated is caused by excessive sparkplug gap, set sparkplug gap at 0.030 to 0.035 Also check for loose plug wires.
High-rpm misfire when system is activated is caused by excessive sparkplug gap, set sparkplug gap at 0.030 to 0.035 Also check for loose plug wires.
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08-01-2005, 03:44 PM
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On Topic of Popping. These are my notes, thoughts and observations:
1) It cant be good if its popping and its not popcorn or a thick booty giving a lap dance.
2) Rich causes popping.
2a) Abrupt throttle snapping close.
2b) Excessively rich condition. Check jetting (nitrous too small for fuel), faulty nitrous noid/wiring, clogged filter, tuning, check fuel delivery, line obstruction, filter(when the last time it was replaced) fuel pressure dropping more than you think, tuning, tuning, tuning.
2c) Excessive plug gap, I would close the gap to min. .035" Normally I run .032-35 NA and Nitrous and never "lost time" from it. Cleaner burn as well.
1) It cant be good if its popping and its not popcorn or a thick booty giving a lap dance.
2) Rich causes popping.
2a) Abrupt throttle snapping close.
2b) Excessively rich condition. Check jetting (nitrous too small for fuel), faulty nitrous noid/wiring, clogged filter, tuning, check fuel delivery, line obstruction, filter(when the last time it was replaced) fuel pressure dropping more than you think, tuning, tuning, tuning.
2c) Excessive plug gap, I would close the gap to min. .035" Normally I run .032-35 NA and Nitrous and never "lost time" from it. Cleaner burn as well.
08-01-2005, 03:48 PM
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the popping is consistent through the run at WOT, there is no popping whatsoever when i let off the gas.
cat3, that is not the discoloration, pic is misleading, that is a shadow, the color difference was clearly visible in person in the red area that i specified. yes i agree with you on the proper reading of the plugs and im not really looking at this as a way to tell if my timing is off as i knew i drove a little through my subdivision after the runs. i was more concerned about the black soot. I really appreciate your help. this is the second plug on the drivers side. this is a TNT f1 kit with the power ring and dual nozzles. nitrous jets are .31 and fuel jets are .18 per tnts recommendation. im still trying to lean towards bottle pressure as my cause of the popping but wanted to post my plugs cuz i didnt like how the soot looked. thanks.
cat3, that is not the discoloration, pic is misleading, that is a shadow, the color difference was clearly visible in person in the red area that i specified. yes i agree with you on the proper reading of the plugs and im not really looking at this as a way to tell if my timing is off as i knew i drove a little through my subdivision after the runs. i was more concerned about the black soot. I really appreciate your help. this is the second plug on the drivers side. this is a TNT f1 kit with the power ring and dual nozzles. nitrous jets are .31 and fuel jets are .18 per tnts recommendation. im still trying to lean towards bottle pressure as my cause of the popping but wanted to post my plugs cuz i didnt like how the soot looked. thanks.
08-01-2005, 03:54 PM
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Close the gap a little.
The soot could be from driving after the run, normal return to rich condition, depending on tune. Timing mark "should" be, or so I recommend, lower, at the cusp of the GS curvature. I like to have it right after the curve on the base side.
The soot could be from driving after the run, normal return to rich condition, depending on tune. Timing mark "should" be, or so I recommend, lower, at the cusp of the GS curvature. I like to have it right after the curve on the base side.
08-02-2005, 08:12 AM
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ok ill try closing the gap if i cant find anything else. bottle pressure can cause this rich condition right? would high or low pressure cause this? i have an incar pressure guage and a bottle heater on the way and i will see how she runs after this. gollum, i could not find that troubleshooting guide. thanks guys for your help!
08-02-2005, 09:30 AM
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Originally Posted by Robert56
Yes, low bottle pressure can cause a rich condition on dry kits.
Robert
Robert
so low pressure could cause a rich condition too couldn't it?
08-02-2005, 09:36 AM
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Originally Posted by Robert56
Yes, low bottle pressure can cause a rich condition on dry kits.
Robert
Robert
Thanks.
08-02-2005, 12:09 PM
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i agree a dry kit shouldnt have that problem. so hopefully my new heater thats coming in the mail will fix this and i can jump up to a 150shot, woohoooo!!
08-02-2005, 07:38 PM
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Originally Posted by Robert56
Sorry, I meant wet kits are affected by bottle press, concerning a/f. Dry kits will maintain a/f ratio no matter how low the bottle press goes, however, you can set dry with a variable a/f and this will be maintained also.
Robert
Robert
Thanks Robert!
