ideal engine temperature

[Dikappa]

Guys,

As my Lambda has trouble getting warmed up, I'm considering different options to do something about this.  i drove it to Fobello, and in fact the only time I saw a temperature slightly over 70°C on the guage was on top of the col d'iseran, 2770 meters...and that was with half the radiator covered up!

I'm not in favour of using the twin scooter thermostat solution, as I feel this in warm up too much blocks the circulation of the coolant by the pump, possibly leading to local hotspots in the engine during warmup.
Another solution is a additional manually operated blind, but that off course would require constand monitoring, and might be overlooked when one ends up in a traffic jam....I know I could....with dire consequenses...

Third option is to build a proper bypassed thremostat solution, which is maybe doable, but will off course not look very original....

But for any solution the important question is: what is a good normal operation temperature to aim for???

[davidwheeler]

I think this is not the sort of question that would have been asked in the 20s when thermostats were unknown and in winter one may apply a muff to the radiator.    I have looked in my vintage motor mechanic books.  The pldest, just post war, does not mention temperature at all.   The 1965 one talks of 155F to 165F which is about 70C.       

[Dikappa]

Thanks David!  I had a hunch 70°C would be fine, I rather have the engine a tad too cool, since coolant circulation is far from ideal as we know!

Koen