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Old Jan 9, 2009 | 07:21 AM
  #16  
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My bet it still on plug gap! Do 9s have iridiums stock? I run coppers in my 8 which I gap down considerably...
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Old Jan 9, 2009 | 07:23 AM
  #17  
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Originally Posted by derekste
My bet it still on plug gap! Do 9s have iridiums stock? I run coppers in my 8 which I gap down considerably...
yeah i believe all evos come with iriduims stock. Last i read, which wasn't recently, there were no copper options for the IX but i could be wrong.
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Old Jan 9, 2009 | 08:19 AM
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its easy to decrease the spark plug gap. do that first and see if that fixes it. fyi 9 sparkplug gap is diff from the 8s. here is the 9s Standard value: 0.5 − 0.6 mm (0.020 − 0.024 inch) you could try around 0.020 and see.
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Old Jan 9, 2009 | 05:12 PM
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yeah I think I will try .5 mm

C6 - 195 grams/sec
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Old Jan 9, 2009 | 05:37 PM
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Originally Posted by tephra
Dan - I just reread your second paragraph - Your not suggesting that my timing going from 4->3 is causing the problem?? but rather the low timing in the first place? (I am still not sure why lower timing results in higher chance of spark blowout??)

I think I get knock if I go from 3->5 degrees of timing. I know it *should* work, since I was running 4* earlier in the pull - but for some reason it will just knock.

edit - I just looked at the log and i am actually getting 1knocksum from the 4031RPM onwards (hence the drop)
If knock is pulling timing deal with the knock. Not only does knock hurt timing and cause misfires but in and of itself can induce misfires. Also that spike is short and quick. It "really" isn't anything that I would be worried about. I really should be asking questions like "how old is the wideband" and "did you ever run leaded race gas". However lets assume for a second its real. 11.4 is not dangerous. If it was I would have lost many more motors over the past decade than I have LOL. Second sure as tootin' you can gap her down. However I *rarely* suggest this unless it is a friend of mine and we are strapped for time and money. The proper fix is upgrading the ignition. An easier fix/test is to just get timing to be proper. Either you coming in too hard with 4 degrees that it is tapering down to 3 or you need to bring in timing harder to go from 4 to 5 degrees. The closer you set spark off to TDC the harder it is for the ignition system to actually do it so the cylinder pressures at are rising at an exponential rate towards the TDC stroke. If the motor will take the timing, give it to her. If not, reduce boost and/or add octane so that it will take the timing. I'm sorry if I'm confusing and contradicting but I hope I'm getting the jist across.
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Old Jan 9, 2009 | 05:58 PM
  #21  
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I dont think 1KS is anything to worry about...

wb is about a year old, never run leaded...

My concern with 11.4 is that if its 1 injector being bad then my actually AFR for that cylinder is a LOT higher than 11.4 because thats the average... its more like 12.1...

I dont think 23psi is a lot either... I will get the plugs gapped to within spec and then retest...
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Old Jan 9, 2009 | 06:10 PM
  #22  
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For 1 KS jack the timing a bit. Also I run 12.5 on the wideband and if I want to go really fast 12.6-12.8.
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Old Jan 9, 2009 | 06:18 PM
  #23  
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the reason the timing is low (well I think), is because every time I tried higher I would get big knock... I even changed fuels because of random knock spikes.. (like 7->14->36) at pk tq...
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Old Jan 9, 2009 | 06:19 PM
  #24  
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If knock is going up with timing, unfortunately your detonating. Honestly I wouldn't change a thing. You probably can't even feel that slight blip. Is it even consistent for consecutive pulls or just a random anomaly?
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Old Jan 9, 2009 | 06:24 PM
  #25  
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yeah well this is the whole thing.

am I getting knock because 1 injector is being bad???!??

I will regap - and retest, that's assuming reducing the gap to 0.5mm (from 0.6mm) will reduce/stop the blowout..
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Old Jan 9, 2009 | 06:30 PM
  #26  
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Honestly I've never had an injector go bad on me. They typically fail at high RPM's and high duty cycles. Not at low RPM with like what 30% duty cycle? Even if they did fail they wouldn't fail for a hundredth of a second. They would just fail. Furthermore the ecu (at least in a DSM, I'd home an Evo is more precise) would throw a P0XXX code. When I was a newb with my DSM an injector clip popped off (due to a service tech breaking the connector for a HG repair for the previous owner). The CEL came on immediately, threw a code, and I had to limp it home. That was all with 1989 technology.
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Old Jan 9, 2009 | 06:39 PM
  #27  
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hrmm yeah I suppose. maybe i just being paranoid
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Old Jan 9, 2009 | 08:30 PM
  #28  
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I vote lc1 acting up or plugs need smaller gap I'm currently running .20-.21 to keep spark consistency at around 30psi. Gap does erode with miles on the plugs.

PS I have seen zeitronix logs with weird jumps in AFR also
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Old Jan 9, 2009 | 08:36 PM
  #29  
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Originally Posted by dan l
Honestly I've never had an injector go bad on me. They typically fail at high RPM's and high duty cycles. Not at low RPM with like what 30% duty cycle? Even if they did fail they wouldn't fail for a hundredth of a second. They would just fail. Furthermore the ecu (at least in a DSM, I'd home an Evo is more precise) would throw a P0XXX code. When I was a newb with my DSM an injector clip popped off (due to a service tech breaking the connector for a HG repair for the previous owner). The CEL came on immediately, threw a code, and I had to limp it home. That was all with 1989 technology.
My injectors went back to vendor and 2 were out of spec. no names of manufacturers but they were inconsistent straight out of the package and when they were flow tested it was proven that 2 flowed less than the other 2 and the 2 that flowed less were not consistent. This problem was diagnosed due to the inability to properly scale the injectors and incosnistent drivability problems, so really not relevant to OP.
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Old Jan 9, 2009 | 09:28 PM
  #30  
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when you say inability to scale the injectors how do u mean?

these are FIC's which means they should be flow tested and matched when the send them out.
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