Hmm...spark plug question plus picture
#16
Formula One Spin Doctor
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That cylinder is burning oil , adding oil to the mix will cause the cylinder to detonate , the plug shows detonation , rich on the top leaner on the bottom and mid. Stick a new plug in their use a no 6 not 7 and run it again pull the plug and look , there is too much mileage on that plug. to use as a good reading tool , a newer plug will give a better idea as to the condition of the cylinder ....
#17
Race Car
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Actually it would be better to swap to #3 as it is on the other injector driver circuit.
However my opinion is that it is probably due to your extended time away and possible a small leak in that valve guide.
I would just change the plugs and pull them after some hard runs and then post up what they look like both a good plug and the bad (if it continues to be bad, I doubt it)
Also the AF gauge will not be able to tell you anything about one cylinder, but it is very valuable for making sure you are at a safe ratio. So yes you NEED one especially if you plan on runnign at these pressures regularly.
However my opinion is that it is probably due to your extended time away and possible a small leak in that valve guide.
I would just change the plugs and pull them after some hard runs and then post up what they look like both a good plug and the bad (if it continues to be bad, I doubt it)
Also the AF gauge will not be able to tell you anything about one cylinder, but it is very valuable for making sure you are at a safe ratio. So yes you NEED one especially if you plan on runnign at these pressures regularly.
#18
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LA- ART
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88" 951 Alpine White
88" 951 S stock
87" 951 Alpine White
89" 951 2.8L
Present Cars
This is where Lart dreams Darwins car will be, but it won't
90" S2
07" Mustang GT
07" Camry SE V6
05" BMW 525i
04" BMW Z4
99" Land Cruiser
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P-car cemetery
(4)944 N/A
86' 951 Silver
86' 951 Red
86' 951 Gray
87' 951 Red
86' 951 Gray
87' 951 Champagne
86" 951 Black
86" 951 Gold
86' 951 Gray
86" 951 Alpine White
86" 951 Black
86" 951 352rwhp 355rwtq
88" 951 Alpine White
88" 951 S stock
87" 951 Alpine White
89" 951 2.8L
Present Cars
This is where Lart dreams Darwins car will be, but it won't
90" S2
07" Mustang GT
07" Camry SE V6
05" BMW 525i
04" BMW Z4
99" Land Cruiser
91" Supra Turbo
67" Mustang "Hot Rod"
#19
#21
Race Car
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The hotter the spark plug the further the electrode sticks into the combustion chamber. example: 5 = hot ....... 9 = cold. colder plugs have the electrode barely protruding out of the threaded area to dissapate the heat quickly
the hotter plugs will burn off any carbon easier for regular street driven type cars
However, if you run too hot a plug in a boosted or High HP engine the electrode will stay hot and may detonate (pre ignite) this is very bad. Hence the reason why when running a highly modded car you need to use colder and change plugs more often.
the "R" is for resistor for interferance
the hotter plugs will burn off any carbon easier for regular street driven type cars
However, if you run too hot a plug in a boosted or High HP engine the electrode will stay hot and may detonate (pre ignite) this is very bad. Hence the reason why when running a highly modded car you need to use colder and change plugs more often.
the "R" is for resistor for interferance
#22
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The hotter the spark plug the further the electrode sticks into the combustion chamber. example: 5 = hot ....... 9 = cold. colder plugs have the electrode barely protruding out of the threaded area to dissapate the heat quickly
the hotter plugs will burn off any carbon easier for regular street driven type cars
However, if you run too hot a plug in a boosted or High HP engine the electrode will stay hot and may detonate (pre ignite) this is very bad. Hence the reason why when running a highly modded car you need to use colder and change plugs more often.
the "R" is for resistor for interferance
the hotter plugs will burn off any carbon easier for regular street driven type cars
However, if you run too hot a plug in a boosted or High HP engine the electrode will stay hot and may detonate (pre ignite) this is very bad. Hence the reason why when running a highly modded car you need to use colder and change plugs more often.
the "R" is for resistor for interferance
Thanks for explaining that!
#23
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No the NGK's numbers work differently the bosch or champion. The colder Bosch would be a WR6DC and the stock NGK 951 plug is a BPR6ES with the 7ES being one rangecolder. Japanese?
#26
#27
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Is that true?? I have only used NGK in racing apps and never paid attention to the stock plugs In any car. But that would be completely backwards
If I am incorrect I apologize.
I must research this ............
If I am incorrect I apologize.
I must research this ............
#28
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#29
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edit...I am incorrect on the heat range between bosch and champion compared to NGK. They are indeed bassakwards.
Boy...... it's a damn good thing I have never strayed from NGK all these years.
Boy...... it's a damn good thing I have never strayed from NGK all these years.
#30
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With american plug makers Autolite, Champion (Bosch included), if it's a higher number it's a hotter plug. Japanese manufacturers like Denso and NGK if it's a higher number it's a colder plug. If you're turning up boost pressure from stock it's a good idea to go one range colder within a + 100HP window.
The 6Es is the stock plug in the NGK, the 7Dc is the stock Bosch.