200 ci temperature

[66Bronc]

What is normal operating temp for most of your 200 ci motors. I already know i need a better temp guage, because stock one is sporadic. I have a 190 degree thermastat in now, can you get less, if so what is least you can get and from where? Warm weather vehicle so i'm not concerned about getting heat to heater core. Main goal is to keep engine cooler, seems to always run over 200 degrees. Thanks
66 Bronc
Virginia

 

[Explorer]

Lower temp thermostat or none is actually worse. It doesn't allow the water to stay in the radiator long enough to cool it. My 200 is being built right now so no help on normal temp, but say 210 should be safe enough. Where in VA? I'm building a 66 half cab right now.

 

[Anonymous]

Put a 180 degree thermostat in it.

What kind of fan are you running & is the engine bored over .030" ? Outlaw

 

[gtm1086]

"Lower temp thermostat or none is actually worse. It doesn't allow the water to stay in the radiator long enough to cool it."

While I do agree that running with out a thermostat can cause an overheat due to the water running to fast through the block which could actually cause steam pockets to form. I disagree with your comment on a lower temp thermostat causing the engine to overheat. Any thermostat regardless of the temp will cause a restriction in the cooling system helping hold the water in the block. The temperature in which it opens only controls what the temp of the water is going into the radiator. If your radiator is in good working condition it will dissipate the heat.

Now for engine temps. I see around 180 to 210 on mine depending on how hot it is outside. When I first started playing around with it I would see in excess of 230 degrees. These are the things I have done. New radiator. Knowing what I do now on this system I would have gone with the largest radiator I could fit in there. New five blade flex fan. 160 degree thermostat. 16 psi radiator cap. New hoses upper and lower. One other item that I have not done yet but it would not hurt would be to build a fan shroud. Other items to look at timing. The engines seem to run cooler with the timing advanced. Set your idle mixture a little on the rich side. Also make sure you have a free flowing exhaust. These last items will also help with the dreaded vapor locking that these motors seem to like.

 

[Anonymous]

Baloney, if the rest of your cooling system is in good condition, you should be able to control the coolant temperature by changing thermostats.

Either your cylinder walls are too thin, radiator clogged, engine cooling system full of rust & the water pump impeller design is not for an air conditioned engine. Good luck on your problem. Outlaw

 

[jamyers]

Stock thermostat is 195 degrees. Note that that's when the t-stat STARTS to open, and any t-stat usually isn't fully open until 15-20 degrees above it's rating. So seeing 225 degrees on a hot day or high load wouldn't be cause for alarm (assuming your cap holds pressure and everything is working halfway decently), unless it always ran at that temp - or takes forever to come down off it once the load is removed.

Back in the day, there was pretty much only ONE type t-stat, unlike today when every year they come up with a new part. Nothing wrong with a 180 degree t-stat, especially if you live where it's warm. I wouldn't go to a 160 degree one, because then you're getting down into the area where the engine doesn't get hot enough to boil out moisture, which leads to accelerated wear.

 

[BIGREDRASA]

Reroute your heater hoses to the driver side, and drop a bunch of degrees (20 or so for me). If you have headers, and the hoses are right above them, they're soaking up a bunch of heat.

 

[JackFish]

We run 160s up here in the Great White North. The came stock like that in the Fairmont.
The only difference it makes is when the thing opens up.
The cooler the thermostat, the sooner it opens.

 

[66Bronc]

Appreciate all the insight> i guess i really dont have any reason for alarm. Stock radiator has been reconditioned and new hoses. Not much room to fit a very big radiator,i guess a better fan and getting some sort of fan shroud would help. Doesnt' take long for engine to get back down to 190 but sometimes easily jumps up to 210 but never more than that really. i still would like to put a better temp guage in and plan to get a 180 thermastat and see what that does.
To Bronco Addict:
This 200 ci is in a 66 half cab i've been building> Live in Harrisonburg, VA. This site has been a life saver on the engine buildup. She's about ready for paint booth. Beginning work on a new drag truck project with Big Block now. Sorry six guys, nothing wrong with having best of both worlds right?

 

[cfmustang]

Reroute your heater hoses to the driver side, and drop a bunch of degrees (20 or so for me). If you have headers, and the hoses are right above them, they're soaking up a bunch of heat.

Interesting. Never even considered that idea...

 

[Eric Rose]

Re-routing the heater hoses helps a good bit.

The best thing is to make sure your radiator is up to the task. The E-bay aluminum radiators are great... I have one and my motor stays pretty constant at 190 using the stock 4 blade fan. Basically the way to success is to get as efficient of a radiator as you can and then you can control the temp with the thermostat as Outlaw said.

 

[jamyers]

The best thing is to make sure your radiator is up to the task. The E-bay aluminum radiators are great...

+1. My story here: viewtopic.php?f=10&t=58405