sgtjd
Well-known member
I rebuilt the heads last April and in the mean time I replaced a lot of other parts. In doing so I noticed a 195 degree thermostat in place. However when you read the shop manual for a 351C it takes a 180 degree thermostat. So I replaced the 195 with a 180. However, last summer was a hot one and occasionally I’ll take the 1973 Mach I in parades. What I noticed the temp gauge was getting hot and had readings in the 90% range. When I had the 195 in there I didn't have such a heat problem. All hoses and connections are new to include all new antifreeze. Water pump in good working order. My question is what would be the correct and safe thermostat temperature based on my situation 180 or 195?