MSD’s new Iridium spark plugs are engineered to improve the efficiency of the combustion process to create the most power possible combined with increased durability. The center tip of the plug is made from iridium to promote the best spark and increase resilience. Call Marken Performance @ 1-888-401-1362 for more info, availabilty. A proprietary ceramic material enhances the dielectric strength of the plug housing forcing the spark, even under extreme cylinder pressures, to jump across the plug gap to the ground electrode. This electrode is machined to expose more spark to the incoming gases to promote the most effective combustion event possible.

MSD Iridium Spark Plugs:
Proprietary plug design inside and out
Designed for use on high performance vehicles that utilize high output ignition systems
Machined electrode increases exposure to the flame to improve combustion
MSD’s proprietary ceramic formula provides the highest dielectric strength
Yttrium ground electrode reduces the chance of pre-ignition
Iridium tip improves cold starts
Designed to outlast other performance plugs on the track or on the street
All spark plugs tested prior to packaging and shipping
Shorty-style plugs for applications where space is limited



1) The center machine ground strap enhanced with Yttrium can withstand the heat associated with high horsepower ignitions like MSD or Accel ignition coils, unlike any other spark plug
2) Believe it or not, spark plugs need to be cooled or they can cause detonation. MSD’s spark plug has a copper core that transmits heat to the cylinder head to help prevent knock
3) This is the business end of the spark plug. Inexpensive materials cause wear over the course of millions of ignition firings. MSD’s Iridium is a must when using a high power ignition in order to keep the spark in its place
4) Spark isolation is important with high output ignitions and MSD developed a proprietary ceramic blend for the strongest dielectric strength
5) By engineering a proprietary copper center core in our plugs we have reduced the heat within the plugs to allow the increase of life on the insulator tip which means you need to change out your plugs less often.

I have NGK Iridium Spark Plugs on my 2006 Mazda 6 3.0L (# TR5IX, # 7397, .6mm tip).
I also have hi-power Accel Ignition Coils!

For more info on Accel ign coils for your 4 cyl Mazda, read: https://www.mazdaforum.com/forum/ele...-mazdas-33895/

Video:

MSD Iridium Spark Plugs - YouTube

Video:

2V 4V Ignition Coil Install Mazda 6 3.0 - YouTube