My R320 started at 8 deg F recently with only a few seconds of pre-glow.
Amazing compared to my previous 300D which wouldn't start at all below 22 deg F, and my 1984 300SD which would crank for 25 seconds after a full minute of preglow at 8 deg F, but would start with no block heater

What I was looking for was faster defrosting when there's ice on the windshield, preferably by heating the coolant via an OEM block heater in one of the freezout plug positions or and/or a conductive heater on the oil pan aftermarket option.

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Bob Roe
Lehigh Valley PA USA
1973 Olds 88, 1972 MB 280SE, 1978 Datsun 280Z, 1971 Ford T-Bird, 1972 Olds 88, 1983 Nissan Sentra, 1985 Sentra, 1973 230.6, 1990 Acura Integra, 1991 Volvo 940GLE wagon, 1983 300SD, 1984 300SD, 1995 Subaru Legacy L wagon, 2002 Mountaineer, 1991 300TE wagon, 2008 Murano, 2007 R320CDI 4Matic 52K, some Hyundai, 2008 BMW 535xi wagon, all gone... currently
2007 Honda Odyssey Touring, 2014 E350 4matic