Rad cap

[Doug&Deb]

Any idea how much pressure I can run for my 52 Coronet? My engine rebuilder suggests a 15 psi cap. I’m concerned about that much pressure on a system not designed for it. My radiator is stock and in good shape.

[Plymouthy Adams]

Plymouth 1950 through 1952 is 4 lb......

 

Note of Importance...the pressure cap was introduced mid year 1950..I do not have a starting serial number....you will know by the radiator design if you need a pressure cap for your 1950 model.

 

Edited September 24, 2018 by Plymouthy Adams

[Dave72dt]

You may want to ask what temp thermostat was installed .  Modern engines tend to run 195 and up thermostats and require higher psi caps.  You don't need or want to run a thermostat in that temp range.  Use a stat in the factory recommended range and the 0 or 4 lb cap (as used by the rad design) will work just fine.

[greg g]

Where is your overflow located?  If it's on the radiator expansion tank or below the cap to rediator gasket on the filler neck it's an unpressurized system and it won't matter what cap you put on as the system can't build pressure.  With a nearly 70 year old core and heater core, I wouldn't go pressurized any way.