Plug difference

[racer15]

What is the difference between W31ES-ZU and W31ES-GU

 

[flattop1]

This may help.

 

[racer15]

Thanks for the help

 

[flattop1]

Duh . Nippendeso spark plug .

 

[Chris Cooper]

Great charts - thanks for sharing !

 

[flattop1]

So taper cut platinum ground strap -zu
Gu lubricated thread for natural gas with u- groove ground strap .