Mercedes states that all specifications are met at an engine operating temperature of 80C! That means that at a temperature of 80C, it should meet all published specs.
The corallary question is: how much above 80C is 'good' or 'better'? I would guesstimate that an operating engine temperature of 80 to 95C is ok (and maybe 'good').
Operating at 110C (is said to be ok) but the engine must (is done automatically) be retarded. So for me, I would like to keep the car as close to 80 - 90C as possible.
In no case does the Cool Harness keep the car below 80C!
Regards . . . . JimF
'94 S500 Cpe
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