Spark Plug problem (newbie question)

[GeoffSmith]

Mystery solved: one of the plugs was cracked, so someone may have dropped one. I don't think I cracked it while installing it as I was ultra careful.

Plugs came form sparkplugsRus.com so may have been dropped while in transit I suppose, although they were well packed.

Oh, well, sorted now and a nice performance boost too.

thanks for your help all-- plenty of info for future reference.

That's why I never throw the last set away - they sit on a shelf in the garage until the next plug change. I learned the hard way though, as I once had a plug with a hairline crack but I had thrown the old set out!

[paulwatkins]

From the holy grail......

What does suffix mean?

Isn't the 1.1 gap for the NA and 0.8mm for the turbo

The suffix is the last part of the catalogue number.

From the above table, the NA plugs and the 'alternative' type (ending in 11 or U11) of plug for the turbo should be gapped at 1.1mm.

The 'recommended' type of plug for the turbo should be gapped at 0.8mm