The guy at the auto parts store said the only spark plugs that are made to be adjusted are ones that have a -11 at the end after all the normal #'s. Have you heard this before.

Also, does anyone have any good spark plug reading web links? I visited the ngk web site already.

Thanks.

 

I don't know if this will help but here is some pics of plug readings.

 

never heard of that all spark plugs need to be gapped to specs ,what ever that plug is being used in

 

I thought these articles were good.
spark
sparky
what spark plug numbers mean And according to this last site, the -11 at the end, means the plug is preset. The plugs that have surface gaps, and double or 4 electrodes arent adjustable either.

 

sparkplug reading

 

I guess i was wrong