Before buying any iridium or platinum spark plugs, do ensure that they are double platinum/iridium, meaning both the center electrodes and ground electrodes are platinum/iridium tipped. There is no point getting normal platinum/iridium where only the center electrodes are platinum while the ground electrode gets disintegrated.

It is the ground electrode that wears out the plug. The spark fires from the center electrode to the ground electrode. It is the ground electrode that gets blown to bits. I have seen that happen on my single iridium and platinum plugs after 20000km in my previous car. In my current car, I wear out the NGK Double Laser platinums (which is the recommended stock plugs for my car) at about 50000km.

This post has been edited by sleepwalker: Dec 6 2011, 11:31 AM

My car manufacturer mentioned it and it came from the factory with NGK Double Plats. Also if you checked NGK they have a products finder page which you can find the recommended spark plugs for your car. They even have a local site at http://www.ngksparkplugs.com.my

There are 3 things to watch for when changing plugs,

1. Plug size/shape (no brainer, size shape can be found in part number)
2. Plug heat rating (you can find that on the model/part number, refer to ngk site)
3. Spark plug gap (which you can re-gap if the model does not have your required gap size).

The most importing thing is the heat rating which has to be the same or equiv with your OEM. So I don't see why it is difficult to find NGK plugs for you car, unless you are driving something that is not on their list.

If the ground electrode does not wear out, none of the spark plug manufacturers would bother with double plat/iridiums would they? Double plats/iridiums also last twice as long as their single counterparts which explains that the plat/iridium plat/iridium ground electrode outlast the normal electrodes. Do you use your turbo for daily drive? My previous turbo did 120k km and the current one has done 150k km and has gone through platinum and iridium plugs like nobody's business.

I wasn't referring to second engine and second turbine.. both are on different cars. Did 120k km for previous car before selling and 150k km on current car. Both on same engine and turbine.