" The plugs that has the Spark arc from the Center Electrode to the side get the single Platinums. The plugs that arc from side to center get the Double. Single Platinum plugs have no Platinum on the side electrodes. "
… and this has WHAT to do with waste spark ignitions?
You have to agree though that by the time most people change their spark plugs, it would be kinda true.
Sure…but it’s NOT because they changed to Platinum plugs that they got better performance. It’s because they swapped out tired worn plugs with new plugs (Platinum or Copper) that they got better performance. If you change out the Copper plugs within the their time interval you won’t have a problem. I agree that Platinum plugs are good for cars that you need/want longer lasting. For a 5 year period I was averaging 55k miles/year. The Platinum plugs were great…I only had to change them once a year. The copper were getting worn after 9-10 months.
My part store wanted $15 for NGK and $5 for Autolite, are they worth it?