Spark plug query

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timmyboy
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Spark plug query

Post by timmyboy »

I bought a service kit for my car, gaskets, filters, plugs etc. Got one of my spark plugs out yesterday (it was a Bosch W4CC). I was supplied with Bosch WR5DC+ and they are about an 8th inch longer (the thead is the same but the extra lenght is the earth electrode protruding farther) than the one already in it. Dunno if this is making sense! Anyway, I've done a web search and I can't seem to find anything about this plug, everywhere I look says I need Bosch W5DC, is there any difference? What does the 'R' and '+' mean?

Can't remember who it is, but someone one here has 'always learning' at the bottom of his posts......I might put 'to much to learn' on mine
:shock:
Gary71
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Post by Gary71 »

Hi

R means resistor, for noise supression, so no worries there. Do a search on plugs on here and you'll find a great chart detailing all the differences.

Not sure about the length difference. W5DC is correct for a 2.4 T not sure about a 2.2 though. Pistons are different as the compression ration dropped in '72, so 1/8th may be important.

Not the complete answer, sorry :)
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