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Does a rebuilt engine run warm until the break in is finished?

I wouldn't stop driving my car at 200 at a stoplight. That's not hurting your engine. The thermostat housing is water leaving the engine.
 
This is a myth that seems to stay alive despite it making no sense.
Conversely, coolant that dwells in the radiator longer also allows coolant to dwell in the engine longer, increasing the heat transfer into the coolant.




:thumbsup:
I definitely have zero flow restrictions. It looks like the Colorado rapids inside the radiator looking through the filler neck.
 
I wouldn't stop driving my car at 200 at a stoplight. That's not hurting your engine. The thermostat housing is water leaving the engine.
200 is pretty fast. Even with an overdrive and tall gears, I doubt you'll get over 160 mph.
 
Actually, they used 2 gallons of concentrate and filled the rest with water.
Straight water with a wetter would have been best, but in the current state I'd be checking the over concentration of AF , which cools poorly
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With the big ole condenser core covering the radiator I don't get a little of flow at idle around 750.

Fun fact, I read somewhere the factory recommended shifting to neutral at stops in traffic during the summer months gir auto transmission cars.
 
Being it's August, and I agree with reply #6, why not just drain a bit of your current fresh coolant, and try a 20/80- 25/75 coolant/water mix until temps ambient/engine drop a bit?
 
So, I just swapped the 180 high flow thermostat to a standard flow 160. It's hard to tell if it helped because I just got back from a test drive in city streets with the AC blowing and the ambient temperature is only 85°F now: it was 95. The gauge never read over 190. The infrared thermometer read about 195 on the thermostat housing.

I went ahead and ordered a factory 6 blade standard flow water pump in case...

That will be the next step if I get higher than 200 tomorrow afternoon.

P.S. I drained about 1 gallon of antifreeze to swap the thermostat and replaced it with a gallon of distilled water.
 
High flow is where it's at. Hope its a Robertshaw/Stewart and not a Mr Gasket - Mr Gasket goes shut when it fails :-/
 
High flow is where it's at. Hope its a Robertshaw/Stewart and not a Mr Gasket - Mr Gasket goes shut when it fails :-/
I forgot that small detail. The high flow thermostat is a Robert Shaw by FlowKooler.
 
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I wonder if there FlowKooler is flowing too fast nit allowing enough time for a thorough heat transfer. I may try swapping it for the 6 fin stock water pump for AC to match the factory AC pulley size.

According to Bouchillon Performance Engineering, the crank pulley is 7-7.5 inches in diameter and the water pump pulley is 5.875 inches for the proper drive ratio.

View attachment 1905538
Personally, I wouldn't replace the FlowKooler yet. Those are good pumps. I have not used one on an ac car, but have run them on 4 of my non ac cars.
 
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