Is a thermostat necessary

[SA-Xplorer]

After reading a thread by Charlie written in 2007 I was wondering if it was necessary to have a thermostat at all in South Africa. At the coldest in winter, the temp gets to about 35 deg F. I notice that in some of the mod threads a lower temp thermostat is used to reduce engine temp. Would this not work better?

Thanks!! Ralph

 

[rookieshooter]

In my modified Bronco 2, I take mine out in the summer and then late fall put in a 190 deg. T-stat. There is no loss of power of any kind or hesitation during those hot summer months with no T-stat. And keeps the same gas mileage also.
Depending on conditions it runs around 155 to 170 with no stat during the summer. It may go up to 180 when towing my trailer.
Plus this low temp. helps in keeping the tranny fluid cooler which is the best thing that can happen to a tranny. Now this is an auto tranny. Heat is the number one killer of automatic transmissions. It's longevity is directly proportional to heat.
I have good accurate Autometer gauges for tranny and engine temp. also.
One other thing is I have a B&M tranny cooler located in front of the radiator.
Since the radiator is running cooler them means more heat transfer from tranny cooler to radiator and then to the ambiant temperature.

 

[aldive]

The simple answer is YES.

 

[BrianDye]

YES. Lol, I found out that mine was stuck open last night, causing my explorer NEVER to actually heat up (Temp needle would NOT move from resting position)

 

[2000StreetRod]

Performance & fuel economy

A thermostat is only necessary if you want to achieve the performance and fuel economy the engine was designed for. The engine was designed to operate at an engine coolant temperature of 190 degrees. To my knowledge there's no place on the planet where it gets that warm (thankfully). The PCM enrichens the fuel mixture when the engine is cold and reduces the enrichment as the engine warms. No thermostat means slow engine warmup and poor fuel economy. Theoretically maximum engine power is produced when the Air/Fuel ratio is 12.6:1 and the engine is warm which reduces friction.

If the engine overheats in warm weather the solution is not to use a lower temperature or no thermostat. That mearly delays when overheating occurs. The solution is to increase cooling capacity by flushing the cooling system, increasing airflow (non-stock fan), replacing a single row radiator with a double row, replacing stock water pump with a high flow.

 

[perth]

Mate im in Aus and we get the same temps roughly as SA i put a thermostat in and even when the outside temp hits 100dg the ex still runs just under halfway and thats with the aircon going.

 

[rookieshooter]

I thought I might add this. I would run one in your stock X because they were designed for one. On my X I always had a t-stat installed. But on my Carburated V8 Bronco, It made no difference at all. In fact it was more responsive with the lower temp. Now I'm speaking of hot summer time temp around 90+ and sometimes 100 or more.

 

[SA-Xplorer]

The engine was designed to operate at an engine coolant temperature of 190 degrees.

Thanks for the insightful reply.

If this is true then why do some guys fit lower temp thermostats so their engines run cooler? Surely this would affect their fuel/air ratio and economy?

 

[rookieshooter]

I know on engine dynos that I have done. Fuel injected engines did like the warmer temps. where as carbed engines liked the cooler temps.
Seemed carbed engines liked 180 and injected liked 190 up to 200.
Might have to do with density of the air in carbed vs. injected engines on this one as far as combustion is concerned.
Running too cool is more rough on the moving parts like cylinder wear and such also.

Just added: Remembering back on my Drag racing days were your time was measured in thousands of a second. We got better ET and MPH when we at least got the engine up to 180 min. Sometime hotter depending how long I sat in the staging area.

And this was with both injected and carbed engines. Injected meaning Old School like Hillborn and Crower were the individual stacks came up thru the hood.

 

[2000StreetRod]

delays overheating

Removing the thermostat or replacing with a lower temperature unit delays when the engine will overheat because the engine is heating all of the water in the radiator in additional to what's in the block. The practice allows a vehicle with substandard cooling to get by on shorter trips. Also, it was a common practice prior to fuel injection systems when fuel mixture control was not precise.

 

[410Fortune]

its also necessary if you like HEAT sometime during your drive, hopefully soon when its 4 degrees out with a wind chill of -30 and 4' of snow on the ground.....yes a thermostat/restrictor plate is required unless you are in a race car

 

[SA-Xplorer]

So a lower temp TS will not inprove performance and consumption then?

 

[410Fortune]

correct
not in a modern computer controlled emissions equipped EFI vehicle

the only reason to use a lower temp thermostat is to attempt to help your cooling system keep up, the cooling system will still reach its maximum tempature no matter when your thermostat opens fully.. the thermostat only controls the lowest possible tempature... keeping the max temp down is up to your waterpump, radiator and fan