How to read NGK spark plug codes

Discussion in 'Engine' started by Blaner, Nov 13, 2011.

  1. Blaner

    Blaner Your Friendly South African Ambassador

    Joined:
    Mar 26, 2008
    Messages:
    3,276
    Likes Received:
    176
    Trophy Points:
    114
    Gender:
    Male
    Occupation:
    Geologist
    Location:
    East London, South Africa
    I have noticed a number of questions lately regarding spark plugs, different codes on the plugs mean different things.

    Here is a nice chart which decodes the codes !

    untitled.png

    So if we take the standard blaster plug which is B8ES, we can interpret it as : B = Thread Diameter : 14mm; 8 = Heat Range: Medium; E= Thread Reach: 19mm; S= Firing End Construction: Standard super copper core center electrode.

    If you have a BR8ES, the R = Construction features: Resistor type, and unless you have a radio that you dont want to cause interference with, the R is not necessary on a bike:)

    Some guys use the B8EG, and G = Firing End Construction: Fine wire nickel center electrode.
     
    Last edited by a moderator: Mar 19, 2014
  2. sicivicdude

    sicivicdude Member

    Joined:
    Apr 7, 2010
    Messages:
    6,172
    Likes Received:
    158
    Trophy Points:
    99
    Location:
    North Carolina
    Good post man!

    It should be noted if you're trying to find a particular plug (cross referencing) to a different brand, NGK uses a reverse heat range number than most any other brand (autolite, ND, bosch, AC delco, champion)

    NGK heat ranges drop as the plug gets "hotter". Most every other manufacturer's part number's work with common sense and the higher numbers are hotter and the lower numbers are colder.... If you are straight cross referencing, number for number you'll be OK as most manufacturers have a straight number to number cross.... If you're trying to get a hotter or colder plug... you'll need to know this!
     
  3. Blaner

    Blaner Your Friendly South African Ambassador

    Joined:
    Mar 26, 2008
    Messages:
    3,276
    Likes Received:
    176
    Trophy Points:
    114
    Gender:
    Male
    Occupation:
    Geologist
    Location:
    East London, South Africa
    that is correct Sic, NGK work backwards for some reason!
     
  4. Prime

    Prime New Member

    Joined:
    Jul 11, 2011
    Messages:
    1,056
    Likes Received:
    15
    Trophy Points:
    0
    Location:
    Batavia, NY
    Sweet post! I can see it being very helpful. Sticky?
     
  5. Braaaptor

    Braaaptor Member

    Joined:
    Dec 1, 2009
    Messages:
    2,169
    Likes Received:
    110
    Trophy Points:
    48
    Occupation:
    Small Engine Technician
    Location:
    Hamlet, NC
    Sticky!

    Great find. I've been looking for one of these to keep around the shop to explain to people how NGK plugs are set up. Now we've got it!
     
  6. slickerthanyou

    slickerthanyou New Member

    Joined:
    Dec 23, 2009
    Messages:
    7,615
    Likes Received:
    137
    Trophy Points:
    0
    Nice post there Blaner! I'll contribute what I have too, same info but comparing the two plugs. EG and ES! If you notice the length of the center electrode is .55in longer, even though they are the same "heat range"(8)!

    [​IMG]
     
  7. Blaner

    Blaner Your Friendly South African Ambassador

    Joined:
    Mar 26, 2008
    Messages:
    3,276
    Likes Received:
    176
    Trophy Points:
    114
    Gender:
    Male
    Occupation:
    Geologist
    Location:
    East London, South Africa
    there we go, thanks Slick, i hope this helps clear up some confusion!
     

Share This Page