Hola Bricksters:
I just replaced the OEM 88 degree C. thermostat with an 82 degree C.,aftermarket one from ManicBoys Auto Parts. The car's temp gauge is now below the middle of the gauge,but with 100 degree F. temps heading our way here in South Texas, I want all the cooling available. I have a 3-row Nissens radiator, new R134 charge,new PAG oil,new orifice tube, new reciever/drier.
I want to ask, will this be too cool for the engine to run efficiently?
Thanks for your opinions.
el Raidman.

Don't put a colder thermostat in your car. It will cause your ECU to dump a richer mixture. Your car will run less efficiently and you might even ruin your 02 sensor and/or cats with a too rich mixture.
Your car has the ability to regulate its own temperature through a proper rad, therm, coolant, hoses, h20 pump, etc. Your car is designed to run in subzero temps, to way over 100. If these are in proper working order, you should have no problems. Don't try to mask a prob by using a colder therm.

That should still be OK. The thing is, you don't really need to replace the thermostat with a cooler one. Logic with older cars said that you had summer and winter thermostats. Much of that was as a result of marginal antifreeze/coolant properties. The modern antifreeze is very good at keeping the car within the correct range. Especially with your 3 row radiator, you should be in business even with the factory 'stat. If all else fails, it runs wide open anyway. It doesn't necessarily give any better cooling, it just keeps things at a cooler temp and gives you a little more range on the temperature gauge.
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Chris Herbst
1992 745, 68k

And others:
93 944, 150k
90 245, 110k
88 744, 160k
87 245, 185k

I'll bet you'll be OK. I mean with south Texas rotisarie (muy caliente)on HOT I'd be driving without a T-stat!

I think sometimes I, too through logic in the hopper...and it typically involves 100°F + temperatures!
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http://www.fidalgo.net/~brook4/oilslubesfilters.html