Hot Rods pressurized coolant systems vs. non...

i'm in the process of making a coolant overflow bottle for one of my cars, and i have a couple questions that i can't research and reason through in my head.
i look at "new" cars, and some have a plastic coolant overflow tank with no vent, so the system is under pressure, others have a plastic overflow tank with a built-in vent tube, so not under pressure.
what is the difference, and which application should i choose? i'm running a warmed up small block 350 in a hoodless/fenderless truck, and i live in las vegas. las vegas = HOT. on an average summer day, driving around in traffic, my coolant temps will be between 190 and 200, that's perfectly fine, i'm just tired of my vent tube ******* out antifreeze on the garage floor when i get back home. i'd like a bottle to catch it and keep it.

can anyone tell me what they have tried and has worked or failed, i'm lookin' for first hand knowledge here, please. any help is greatly appreciated!

-tred

 

If you have an adequate size radiator and don't fill it completely full, it should not puke anything. I was just in Vegas yesterday with my flathead 6 Hudson, no water loss, and yeah, it was kind of warm.

If you want to keep the radiator full, get a large capacity overflow tank, and run a tube from the radiator neck fitting to the bottom of the overflow tank.

Modern cars have a different setup, the coolant tank is pressurized, it acts like a larger upper radiator tank. There is no need to do something like that with your car, unless the radiator is just too dang small for the car.

 

In the 50's you did not fill the rad.. Leave it 1" down and run a 7# cap. I've run that way for 7 years with no recovery system. BTW recovery tanks always are open to atmosphere, the cap lets the coolant back in..