Iridium Spark Plugs

Discussion in 'Performance Mods' started by cosworth, May 29, 2013.

  1. cosworth

    cosworth Member

    I'm currently running an NGK B6HS and would like to switch to an Iridium plug. NGK says they don't have one comparable to my plug in Iridium. Anybody have any luck finding/using an Iridium plug? If so what make and part number please.

  2. HeadSmess

    HeadSmess Well-Known Member

    please state three reasons WHY you feel iridium is a better plug (on cheap 2 strokes) to use?

  3. Fabian

    Fabian Well-Known Member

    My experience has shown that an Iridium spark plug performs no better than a standard copper core spark plug; in fact the Iridium plug that i tested didn't last all that long before it started breaking down and consequently gave the engine annoying misfires.

    I have gone back to conventional NKG B8HS plugs for my application.
    Last edited: May 30, 2013
  4. cosworth

    cosworth Member

    It was suggested as a compliment to the Jaguar CDI for best performance.
  5. cosworth

    cosworth Member

    Thanks, I appreciate your input.
  6. Fabian

    Fabian Well-Known Member

    and i use a Jaguar CDI on my bike.
  7. cosworth

    cosworth Member

    I will learn from your experience and stick with my NGK.
    Thanks again for the input.
  8. HeadSmess

    HeadSmess Well-Known Member

    :jester: i asked for THREE reasons! not one! :jester:

    ok, iridium plugs are designed to be fitted to engines such as mitsubishi V6's. they have a service life of 100,000 km.

    the rear bank of cylinders on a mitsu V6 is under the intake manifold. this requires a lot of work to get to the plugs. way to much work for every 10,000km service. the front plugs are standard. the rears are not.

    theyre also used in modern motors for the same reason...they reduce service intervals. when you see where some manufacturers place plugs nowadays, youre thankful for not having to change them too often.

    they also can be run a lot hotter than standard plugs, as platinides have the highest melting temperatures amongst most metals. that is platinum, rhodium, iridium... theres a few others that id have to refer to a chart to recall :(

    platinum i believe is roughly twice the value of gold. its the most commonly occuring platinide. iridium? double the cost again.

    meaning the plug is expensive.

    there are no performance benefits. a spark in a cylinder is a spark, no matter what. it does the same job regardless.

    good decision. just stick to standard NGK "B" series...
  9. Fabian

    Fabian Well-Known Member

    not to mention that the "B" series NGK plugs seem to work just as well if not better (in my personal experience) and are approximately one tenth the price of an Iridium spark plug as well as being the non resistor type :grin5: