MaineShark
Well-known member
- Joined
- Sep 21, 2002
- Messages
- 1,326
- Location
- Rockingham County, NH
- Corvette
- 1979 L82, 1987 Buick Grand National
Seems to be a lot of confusion about exactly what the thermostat does.
The basics: the thermostat is a temperature-controlled valve that keeps the coolant from leaving the engine block when the coolant is below a certain temperature. When the coolant goes above that temperature, the termostat diverts it out to the radiator.
In operation, the termostat regulates warm-up, and sets the lowest operating temperature of the engine. It goes something like this:
*Start the engine.
*The coolant is forced to remain circulating in the block.
*Heat from combustion heats the coolant quickly.
*Soon, the coolant reaches the thermostat temperature, and the thermostat diverts it to the radiator.
*Now, the coolant is transferring heat to the air and losing temperature.
*If the radiator is efficient enough (say, a really cold day), the coolant may drop below the thermostat temperature, which causes the thermostat to limit it to flow inside the block again, until it warms up.
What it all means is that the lower the thermostat temperature, the longer it takes the engine to warm up (since it only gets an "assist" until the termostat temp - after that it has to fight the radiator to warm itself), and the lower the engine might go, if conditions permit.
What it also means is that lowering the thermostat has no affect on the upper temperature limit.
Now, some people may not care about a quick warm-up, but remember that you shouldn't start pushing the car hard until it is warm, so a long warm-up means delayed fun. More importantly, though, is the limit the thermostat places on the minimum operating temperature. Too hot is bad for you engine. But so is too cold. Dropping in an extremely low-temp thermostat can allow your engine to run colder than it should, increasing wear and leading to a shorter life.
So, what's a 'Vette-lover to do?
Well, I'd say that we should take a lesson from the General. Current tehrmostats are generally 195. This makes the engine run a little bit hotter, which lowers emissions. Pre-emissions, the thermostat temp was 180.
If emissions is not a big worry, I'd say that 180 is best. That keeps the engine from getting too cold, warms it up quick enough, and won't push it hotter than it needs to be, either.
I can't think of any time when a 160-degree thermostat came from the factory, and I can't imagine why anyone would want a street car to run that cold, since the engine wear would be increased dramatically, warm-up would take longer, and any gain in performance due to lower operating temp would be small, when compared to the shorter performance life of the engine.
Joe
The basics: the thermostat is a temperature-controlled valve that keeps the coolant from leaving the engine block when the coolant is below a certain temperature. When the coolant goes above that temperature, the termostat diverts it out to the radiator.
In operation, the termostat regulates warm-up, and sets the lowest operating temperature of the engine. It goes something like this:
*Start the engine.
*The coolant is forced to remain circulating in the block.
*Heat from combustion heats the coolant quickly.
*Soon, the coolant reaches the thermostat temperature, and the thermostat diverts it to the radiator.
*Now, the coolant is transferring heat to the air and losing temperature.
*If the radiator is efficient enough (say, a really cold day), the coolant may drop below the thermostat temperature, which causes the thermostat to limit it to flow inside the block again, until it warms up.
What it all means is that the lower the thermostat temperature, the longer it takes the engine to warm up (since it only gets an "assist" until the termostat temp - after that it has to fight the radiator to warm itself), and the lower the engine might go, if conditions permit.
What it also means is that lowering the thermostat has no affect on the upper temperature limit.
Now, some people may not care about a quick warm-up, but remember that you shouldn't start pushing the car hard until it is warm, so a long warm-up means delayed fun. More importantly, though, is the limit the thermostat places on the minimum operating temperature. Too hot is bad for you engine. But so is too cold. Dropping in an extremely low-temp thermostat can allow your engine to run colder than it should, increasing wear and leading to a shorter life.
So, what's a 'Vette-lover to do?
Well, I'd say that we should take a lesson from the General. Current tehrmostats are generally 195. This makes the engine run a little bit hotter, which lowers emissions. Pre-emissions, the thermostat temp was 180.
If emissions is not a big worry, I'd say that 180 is best. That keeps the engine from getting too cold, warms it up quick enough, and won't push it hotter than it needs to be, either.
I can't think of any time when a 160-degree thermostat came from the factory, and I can't imagine why anyone would want a street car to run that cold, since the engine wear would be increased dramatically, warm-up would take longer, and any gain in performance due to lower operating temp would be small, when compared to the shorter performance life of the engine.
Joe
