If boating sal****er, the temp is normally 160. But fresh water, you could
raise the temp to 190 and get better performance / milage. The 160 stops
precipitation of salt on to the engine cooling passages. Go to a decent
auto parts house and ask for a 160 or 190 thermostat for a 5.7L Chevy. Or
take the old one with you.
Bill

"OSU" wrote in message
ervers.com...
whats the correct operating temp for a 98 Merc 5.7 V8 RWC Carb pushing an
alpha drive, and whats the correct T-Stat for this engine

Thanks