Coolant Overflow Tank

[MV8]

It is on the cap. Oem probably 10-13psi, but the radiator and heater core can probably handle up to 16 psi. I'd run 13.

Make sure the gasket is in the cap to fit against the top of the radiator neck or it won't siphon very well. Sometimes they get pulled out.

 

[MOPAROFFICIAL]

I’ve used for years a cleaned out quart oil can with a 3/4” hole in the cap zip ties to the radiator support. The tube drops in and leave an air gap. I can read the clear sight line to tell when I need to empty it.
Local tracks have had no issues doing this. Again - keeping the antifreeze off the raceway.
But if you want to be fancy….

Vitamin water bottle here LOL
Had to have one for the track.
Gonna hook up a real tank soon I've had laying around for yrs.
Mine never spews out though.