300celvr, I use Bosch F8DC4 plugs in our 300CE's with the same 104 engine per the local MB dealer's Service Department recommendation ... and the engines run fine. Go to benzautoparts.com and check the pricing on Beru ignition wires with the 90 degree shielded plug connectors. As far as I know Beru were the factory-installed wires. Our 1992 300CE had them when purchased used at 27,000 miles.

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Fred Hoelzle