BOSCH plugs Gaps

[lofty]

I have recently added a page to my web site on servicing the 'A' Class with photos from another owner as well as my own.He changed his plugs at 23000 because they were not sparking on all three of the contacts on each plug .
As a result of his findings and bearing in mind that my car is up to 30000 I purchased a new set of plugs myself only to find that the gapes on the plugs vary so much that you can see it even with the naked eye. My Son being a tool maker then measured them on a shadowgraph, of the twelve gapes only two were the same. I have contacted BOSCH who at present will not come clean on what the gap should be? Does anybody know what gap should be present on NEW plugs suitable for the 'A' Class 160. BOSCH responcs:-

The plugs you have are triple electrode, copper core plugs, they are NOT
able to be gapped. There is NO tool on the market to gap these plugs.
If the plugs have been damaged and thus the gaps are now incorrect and
inconsistent, they are not able to be used.

If you are unhappy with the status of the plugs, please return to
purchase location.

I would like to know what makes BOSCH think that replacements would be any different?? I am in touch with MB as well to see if they will come up with an answer.
For further info go to :- http://homepage.ntlworld.com/albert.rowe/mypage.29.htm
lofty :wink: