the Sachs "tropical duty" VFC is for M104's and will lock at around 90C. this effectively turns the cool harness into a failsafe instead of an active component in the cooling system. i am tempted to order one. the VFC mod that JimF has on his pages locks the VFC via the added screw (they don't have a "tropical duty" VFC for the V8's). maybe in the future a VFC bimetal strip replacement/upgrade will accomplish the same thing..
1993 300e-2.8 - gone now <sigh>
"Do not adjust your mind, it's reality that's malfunctioning"