what should the difference be between top

[freshayr]

how much temp differential should there be between the top and the bottom of the radiator? i.e. how many degrees are you typically lower the temp of the coolant as it pases throught the radiator?

 

[cavemanmoron]

how much temp differential should there be between the top and the bottom of the radiator? i.e. how many degrees are you typically lower the temp of the coolant as it pases throught the radiator?

Good question!! I have no clue, but do know a thermostat
is helpful to slow the coolant flow down slightly.

I guess you could put digital temp sensors at the top of the intake,
and at the water pump inlet, to find out for sure.

 

[Mrmopartech]

You can test this with a snap on lazer thermal gun.I use this to see the difference in temps in differnt areas on the engine and cooling system.You will see a drop of about 40-50 degrees depending on how much air is being pulled through the rad at the time.At idle the top will read the most and higher due to heat rising in the rad,the more air being pulled through the rad at idle removes the heat and the cooler water drops to the bottom to be pulled into the motor by the pump.Your thermostat is the timer for how long the water will stay in the rad to be cooled.A 190 thermostat can help cool your motor better as it will allow more time for the coolant in the rad to cool down as long as the fans are going full tilt.Running the motor at 190 is not a problem,as most modern cars run the motors with 195 thermostats and the cooling fans only come on at(230F).Your biggest thing is to get the fans that pull the most CFM and can fit in the engine bay with little or no work,and make sure you can flow as much air into the rad and not have it go over the top of the rad between the hood and the rad support.Mrmopartech