Spark plug info

1. Use oem recommendation

2. Copper cheapest plug, 20k-50k mi

3. Platinum better , 80k -90k mi.

4. Double platinum better . 80k-100k 

5. Iridium best long life, 120k mi

 Oem multi ground  replace w/iridium

6. Subaru, Nissan, Asian, Honda use ngk plug

7. Ford use Autolight

7.5 Chevy AC Delco

8. Ohm check 4k-6.5k on center resister 

Center to ground 0 ohms

9. Chrysler / Dodge use Champion

10. VW / NGk

Bosch on European only