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  1. #1
    "Stock Car" 99cobra09's Avatar
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    .054 Spark Plug Gap Missfire

    I just did the spark plugs and i have always ran the gap at .045, well i did them this time at .054 and theres a miss when the engine is in load. Most of the people here runs them at factory gap but i guess mine dosent like it, this isnt normal is it. Is it because im running a higher compression 10.1?
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  2. #2
    built,novi2k,T56,solid qwik01cobra's Avatar
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    .45 or bust on N/A car


    -Chad-

  3. #3
    The Shocker IUP99snake's Avatar
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    I had a similar problem. I had plugs that were gapped at .54, and I had a real bad misfire in the higher RPM's. I gapped em down to about .37 and it fixed them! With an N/A car you might not need to gap them that small. .45 for an N/A car sounds about right.

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  4. #4
    NA FTW Chris _Scott's Avatar
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    funny, i was having misfirings from gaping mine too small..they were at like.. .027
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  5. #5
    "Stock Car" 99cobra09's Avatar
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    Quote Originally Posted by Chris _Scott View Post
    funny, i was having misfirings from gaping mine too small..they were at like.. .027
    .027 is for like FI applications!

    What do you run them at now?

  6. #6
    say no to power adders na svt's Avatar
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    Autolite 754s, .54" gap with 10.8 to 1 here, no problems.

  7. #7
    NA FTW Chris _Scott's Avatar
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    Quote Originally Posted by 99cobra09 View Post
    .027 is for like FI applications!

    What do you run them at now?
    Yup, they came out of another car and just tossed them in [I was just making sure that the spark plugs I had weren't bad]

    I recently just pulled them out now, and they're gaped around .040, I will be spraying nitrous.

  8. #8
    "Stock Car" 99cobra09's Avatar
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    .040 i think is a good gap for nitrous, how much are you spraying?

  9. #9
    NA FTW Chris _Scott's Avatar
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    I am not spraying yet..but I will only be spraying a 75-shot, if that. Because I am still on a stock shortblock, so after the carb and spray I'll be at 460-475ish to the wheels.

    On the new shortblock.. 100-150 and will gap them closer for that.

    I have the nitrous kit just chillin in my room, waiting for my carb'd swap to get done so I can put it in!

  10. #10
    "Stock Car" 99cobra09's Avatar
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    You definately have to make a thread of you carb swap, not many people go with that route but its going to be interesting!

  11. #11
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    Quote Originally Posted by Chris _Scott View Post
    I am not spraying yet..but I will only be spraying a 75-shot, if that. Because I am still on a stock shortblock, so after the carb and spray I'll be at 460-475ish to the wheels.

    On the new shortblock.. 100-150 and will gap them closer for that.

    I have the nitrous kit just chillin in my room, waiting for my carb'd swap to get done so I can put it in!

    I have my nitrous kit sitting in my room on the floor too! ;P Need it put in -.- I don't trust myself doing it lol.
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  12. #12
    "Stock Car" 99cobra09's Avatar
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    Nitrous is one thing that you really have to know what your doing. its very tricky!

  13. #13
    SVT God
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    a couple of the Die hard guys here ( na svt and Quad) say .054, I've never ran any Stang with a gap that Big even with an MSD box, I'm at .048 now!

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