Any Advantage Going to Higher Temp Thermostat?

[LegacyT]

I have a late 80's carbed 5.0L raw water cooled engine in my boat. It's run in fresh lake water. I know the stock thermostat is a 140* one. I see optional 160* and 180* ones available. Is there any benefit to running a higher temp one? Combustion efficiency or carbon build up?

 

[jerryjerry05]

The engineers at Vovo/ General Motors put a 140 in for some reason.
The only benifit I could guess is if you had a water heater added to your system it would make the water hotter

 

[JustJason]

If you have raw water cooling and run a high thermostat you run the chance of mineral buildup inside of the block in freshwater, and you will definitely get salt build up inside of the block in saltwater. That's why raw water cooled blocks have to run cooler.

 

[dypcdiver]

JustJason has given the correct answer.
However the recommended stat for the raw water cooled 5.0 Gi is 160 deg and essentially it is the same engine. I had a season of running at 130 -140 deg due to a blocked bypass in the stat housing resulting in a permanently rich mixture.
When eventually I fixed the problem the engine ran much better and with more power. The ECU was over fuelling it, I suspect it sensed a cold engine and added the equivalent to choke.
If it was my engine I would be inclined to try the 160 deg stat. It would be interesting to get a read out of the mineral content of the lake water you boat in, calcium being the main culprit of scale build up.