How low are your plug gaps?

Syphrus

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So I've spent the last 2 weeks tracking down possible issues only to find that my si(full bolt on, stock turbo, ethanol flashrpo basemap) misfires at high rpm until gapped down to .016". It was stuttering/misfiring in boost even at .018" just wondering what gap everyone runs? That doesn't seem normal, anyone know why it may be this way?
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Syphrus

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Yeah, PRL's post is what really had me worried. Lol. I figured I could do with low end of stock gap(started at .028, no good. .025, .020, .018, better as I went down, but all had misfiring in higher boost) these plugs were new, but running them for a week at .028 may have depreciated them some. But still seems strange. I'm in the process of replacing the injen intake, maybe the rich trims could be requiring lower gap? At .028, the car was running like crap even with stock intake and stock tune. ?
 

Sport-injected

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I'm at .030 with the RV6 turbo at 26psi with 93 octane and no issues. I started at .026 and worked up to .030. so far so good.
 
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Syphrus

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Yeah, that's well over the compression I'm making, so I can't imagine the spark is blowing out. I'm back on stock coil packs now, I should be getting my ignition project coils warrantied in the next few weeks. Maybe all my coils are weak. I'm really stumped, but I had been through boost leak tests, compression tests, multiple tunes, stock intake, different fuels. I'm concerned needing the gap that low is just appeasing an underlying issue.
 


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Yeah, that's well over the compression I'm making, so I can't imagine the spark is blowing out. I'm back on stock coil packs now, I should be getting my ignition project coils warrantied in the next few weeks. Maybe all my coils are weak. I'm really stumped, but I had been through boost leak tests, compression tests, multiple tunes, stock intake, different fuels. I'm concerned needing the gap that low is just appeasing an underlying issue.
Is that those $600 10 times sparker coil packs? I wonder how things would be on the stock coils and a less aggressive gap. Seems like these aftermarket coils provide great benefits half the time and weird issues the other half.
 
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Syphrus

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Yeah, they came with the car. One completely failed and they are less than 3 months old. But it failed while I was letting it misfire in high rpm. Possible that I fried it trying to pull too much. That was when plugs were at .028. The stocks are what is on it now, and what I've been doing the gap testing with. Only real benefit with the warrantied coils is I know they are new. In the research I've done, they have a lot of hype and fan boys but one test showed they were basically rebranded Bosch with identical performance.
 
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Syphrus

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Head gasket. Endoscope shows coolant coming from head gasket. Lowering gap just masked the issue probably by lowering the compression.
Honda Civic 10th gen How low are your plug gaps? 20210613_162043
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