Originally the 1969 Riviera came with a 190 degree thermostat from the factory. If a new one is needed which one would be the best choice (160/180/195) ? Thanks.
Hi, rockauto.com says the 195 thermostat as to be an OE thermostat replacement...a little confused now as to what i should order? Btw: my car is all original, nothing modified, no racing etc.
The thermostat sets the operating temperature of the system. Do you want the engine to run at 180* or 195*? It's just that simple.
I understand that, so at normal operating temp there is no difference? Or does it run a bit cooler at normal operating temp?
No, the thermostat tries to keep the temperature at the stat rating. If you want the coolant temperature on the gauge to read 195* or more fully warmed up, choose the 195 stat. If you want it to run closer to 180*, choose the 180 stat.
Thanks. Is there any advantage for my stock situation to lower temp t0 180 on the gauge? Is it better for the engine?
Higher coolant temperatures are better for emissions, gas mileage, and oil cleanliness. They are worse for oil pressure, and tendency to detonation. Running an engine at higher temperatures is better for power PROVIDING you can keep the engine out of detonation. That's why newer car engines have 195 stats. Those newer engines also have microprocessor controlled fuel injection and ignition timing with knock sensors. Cooler running intake air is better for power as well. 160* is too cool. I think 180* is the perfect compromise. That is what I run.
Thank you Larry, your engine situation is far from original right? So for my original/stock situation you would still recommend 180 over the 195 thermostat?
How do you drive the car, like a little old lady, or do you drive it aggressively? How about climate? Do you live in an area with consistently high temperature, or cold? I am not going to recommend one or the other, you make that decision based on your preferences. Just don't expect the engine to run cooler than the thermostat you select.
I drive it mostly normal, not aggressivly nor like an old lady. It is like NYC climate here, mostly not that strong winters though, and summers last a bit shorter here. My car is stored inside from november to about march early april. Thanks.
Either stat will work fine for you but, if you have A/C and drive in stop and go traffic during the hot summer months, I'd go with the 180. Also, if your motor is old and oil pressure is less than it was when the motor was new, the 180 is also better since it allows oil pressure to be a little higher. If none of the above concern you then stick with the factory replacement or a 190.
