At 11:12 PM 6/3/2011, Rocket J Squirrel wrote:
>I really didn't want to take the darn water pump out to replace the
>thing so I've had it in there since.
>
>I asked Steve, of Steve's Place, here in Bend, Ore., what he thought and
>he said, "the higher temp one was to pass emissions in California. The
>engine will last longer with the lower temp one."
>
>Well, I didn't know so I set that matter aside.

It may be of interest that the same thermostat is specified for all
versions of the 1.9l and 2.1l engines in Germany and the US.  025 121 113 F.

Smokey Yunick was looking forward to the day when engines would be
ceramic and run at red heat.  Would take some fancy footwork for
connections to the rest of the universe, but the engine would run
more efficiently.

Under-temp engines have trouble getting rid of crankcase acids and
such condensate-related troubles.

Pressurised cooling systems were invented so engines could run at
boiling-water temps.

I think if you cast your net a bit wider you'll find a very broad
consensus in favor of running this (and any) engine at the
temperature the maker intended.

YMMV...

Yours,
David