Spark Plug Question
 

Copper or Platinum?

NGK or Bosch??


Did a search, but didn't really find anything that is swaying me one way or the other.

Silver

Forget modern platinum with the wire-sized center electrode.

The Bosch set has known heat ranges for their use in Porsches. You never how how equivalent the heat range overlap is when you go with non OEM vendors. Copper widens the tolerable operating range and silver extends this a bit further...but I don't know if the silvers wear out faster. Luminaries like John Walker also like the copper NGK and these aren't a bad choice if you nail the heat range. Have nice finish to the rolled threads, too.

Wil

Silver electrodes have excellent life span, copper does also. With todays no lead fuels the plugs last a long time. Copper is cheaper and easier to get. Can"t go wrong with OE.