give the run down on plug gaps

Discussion in 'Technical' started by stmanser, Oct 23, 2005.

  1. stmanser

    stmanser Looking for a Maverick

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    i had my plugs gapped at .040.. last night at the track a friend says gap to .050 and we did... the car went a slower time but a fast mph...

    now i hear that .050 is way to high

    i am runing a complete MSD ignition..


    timed at 37* at 3000 and the advance is set at 3600 rpms..


    . 6a box...
    blaster ss coil.
    8.8 wires.
    pro billet dizzy
    and autolite 666 plugs

    . pump gas last night


    someone give me the good run down on the igntiion setup please... i am running a lot slower than the 14s i should be running
     
  2. Grabber71

    Grabber71 Milique Toast

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    I gap my plugs at .040 to .045, depending on the plug and heat range. I am using a MSD setup as well. I was always told the MSD has a hotter spark than stock and so does not require a big gap...also that the spark will try and find the easiest point to escape so your system will need to be in top notch shape if you tax it to the limit. What kind of cam are you running?
     
  3. stmanser

    stmanser Looking for a Maverick

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    xe256h comp cams xtreme energy

    Basic Operating RPM Range:1,000-5,200 RPM

    Intake Duration 050 inch Lift:212
    Exhaust Duration 050 inch Lift:218
    Duration at 050 inch Lift:212int./218 exh.
    Advertised Intake Duration:256
    Advertised Exhaust Duration:268
    Advertised Duration:256 int./268 exh.
    0.477 int./0.484 exh. lift
     
    Last edited: Oct 24, 2005
  4. don graham

    don graham MCG State Rep

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    i run mine at a 35-37 gap. i've been told that you want to make it easy for the spark to work. but that's at the track. i run an msd 6al, blaster II coil, msd distributor.:)
     
  5. stmanser

    stmanser Looking for a Maverick

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    ok...thats what i thought....but i was told by an "expert" friend of mine at the track saturday to gap higher if the ignition can handle it...

    this is why i need to get with you and dennis on a regular basis.... to talk to the maverick guys who know what they are talking about...


    once i get my car consistant.... i want to join up with your team don... if you will have me
     
  6. ShadowMaster

    ShadowMaster The Bad Guy

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    Ok...you increase the gap and it slows down. Simple...put the gap back where it was and see if the ET returns. If it does...your friend is wrong and you learned something about TESTING. Just because someone is adamant about their opinion doesn't make them right. Your "expert friend" was wrong and you certainly didn't need to wait to get on here for verification. Different engines will want different things. You can get close with recommendations from others with similar setups but your ultimate setting will come from testing. By the way....last engine I did like yours wanted nothing higher than .040" gap. I usually gapped them at .038" and let it eat. (y)
     
  7. MiteeMaverick

    MiteeMaverick Senior Member

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    mine likes .045 better than .048 or .050, different combos, fuel, timing, you just have to find what your car likes.
     
  8. ratio411

    ratio411 Member

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    Faster mph means more HP.
    Maybe you ran a slower ET because you lost some traction...

    I have heard it both ways on the plugs, well actually only one way for electronic ignition and one for MSD.
    I have been told to run as much gap as you can.
    Yet I have been told that an MSD works better and lives longer with a little less than you can get away with on other electronic set-ups.
    So, where cars today can run .050" without trouble, sounds like .040" might be the way to go with MSDs.
    Nothing concrete, just my .02
    Dave
     
  9. stmanser

    stmanser Looking for a Maverick

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    ok... sounds great... and yeah.... thats why they call it Test n Tune...

    now what about running purple gas with it.... i talked to another mav guy named dennis sat night...h says he runs pump gas and runs very well in the 12.4 range consistantly.... if i put purple (108 octane i think) i can tell the car likes it... it runs better overall..


    i was going to try it sat night... but funds ran out...
     
  10. ratio411

    ratio411 Member

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    What compression ratio are you running?
    One thing everyone should know about high octane fuel is that it actually hurts performance unless you need it.
    Higher octane rating just means the fuel burns slower. This is NOT optimum for performance unless you just can't run lower octane without preignition.
    Dave
     
  11. stmanser

    stmanser Looking for a Maverick

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    compression ratio is unknown... i told the guy who sold my the pistons i wanted 9.5:1 pistons... the engine shop fed me a lot of crap so i am not sure i even have those pistons or not...

    heads are D5OE which is a 58 cc head... and the pistons should be 9.5:1 i havent done a compression reading in awhile so i dont know ...


    tell me what you need to figure it out...
     
  12. don graham

    don graham MCG State Rep

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    with 9.5-1 i'd sure be using the pump gas. the only thing i might do is get the high test. sure will save you $$$in the long run. i run sunoco purple (106 octane), but i've got 11-1.my engine builder said either vp-110 (107 octane) or sunoco purple. :)
     

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