Post by nisse on Mar 1, 2010 18:49:09 GMT 8
Hello bro, IK16 is known as "warm" plug whereas IK20 is classified under "colder" plug. How do you know whether is your combustion is completed? Remove the plug and see. The gnd electrode should be "chalky white". As a rule-of-thumb, the DENSO recommended IK16 as an equivalent is correct based on the assumption that there is no mod done - meaning engine is stock condition. depending on the magnitude of your mod-up, most ride should falls within IK16 on local road - meaning 5500rpm on every gears. Unless you headed north where u need to use 2nd/3rd/4th gear very often and rev up to 6000rpm, then go for IK20.
when u use IK20 and noticed that it covered with black deposits - meaning that the plug is too cold - meaning incomplete combustion. WHY? becos you didn't rev high enough. The combustion temp is less than 500 deg C. For IK20 to work properly, your combustion temp should be at least 600 deg C and above.
anyway that's what I've experimented and observed and thus share.
Hi bro, thanks for sharing.
I read about spark plug condition from this site. www.4secondsflat.com/Spark_plug_reading.html
This is the extract fro the website...
'#3 The threaded portion of the plug gives you the heat range, look at the threads you'll see that a few toward the tip are a dull burnt looking color the rest are black and shiny. You want about 2 threads showing the heat on the end of the plug and the rest of the threads to be shiny, this plug is impossible to read because of the oil mess. If you using a longer reach plug than this one 2.5 to 3 threads is optimum.
To increase the number of burnt threads increase the heat range of the plug, if you have 4-5-6 threads burnt you need to get a colder plug.'
Using IK16 fits the 'optimal' condition of having 2 burnt threads on my Cerato. The gnd electrode was also chalky white.
I usually do short trips and the longest is not more than 150km (when driving in Malaysia) and I hardly rev above 5k RPM.