Denso Iridium Power A+++

[mechtech2]

When you have a U Groove, you only have precious metal on one side.
This will wear great in 1/2 of a waste spark ignition, but the other 1/2 will wear like a normal steel plug.
Thus the short life.

 

[dailydriver]

Originally Posted By: mechtech2
When you have a U Groove, you only have precious metal on one side.
This will wear great in 1/2 of a waste spark ignition, but the other 1/2 will wear like a normal steel plug.
Thus the short life.


This is why.^^^

No one puts a split precious metal pad on either side of a u groove ground electrode (at least I've never seen or heard of one) ONLY on regular, old, FLAT ground electrodes, hence the greater wear to the un-padded u grooves (even in a non-waste spark, individual coil pack, coil on/near plug system).