Why do we need the Radiator tank ???

The Pantera system as designed has two tanks, a swirl tank and an expansion tank. The expansion tank functions like all the little plastic tanks on cars since the early 70s. The swirl tank creates a vortex that seperates air out of the coolant before it goes to the radiator.

You can eliminate at least one by using a modern style expansion system. You move the expansion tank to the waterpump inlet and a small bleeder tube to the inlet side top of the radiator. New cars have the rad below the engine so they cant get the air out of the radiator easily nor can they be checked with a conventional cap. So new cars have the cap on an expansion tank that is under pressure. The idea is that a small flow of coolant passes from the top of the radiator to the expansion tank and back to the water pump inlet. And I mean small, like a 1/8 inch hole. Any air trapped in the radiator passes to the expansion tank and the tank passes coolant to the waterpump inlet. Keep the tank 1/2 full and you are fine. Same principle can be applied to a Pantera.

Right on Dave.

The tank which the motor outlet hoses connect to is a "swirl tank" its job is to remove air from the coolant. Do you need it? Some race car designers think so, but not all. There's a lot of street cars running around without one. Swirl tanks don't normally have radiator caps, just an air bleed on top plumbed to the "expansion tank". The Pantera's overflow tank looks a lot like an expansion tank, except its not plummed to the suction of the water pump as an expansion tank should be.

Your cars coolant system needs some way for coolant to be relieved as it expands from heat, and to be drawn back into the system as it cools. One method is the familiar overflow tank which is open to atmosphere and connected to the radiator at the radiator cap. As Dave points out, the more common design is now to use an "expansion tank" connected on the suction line between radiator outlet and water pump suction, or connected to the water pump directly at a low pressure (suction) tap. The expansion tank will have a radiator cap and becomes the high point & fill point for the coolant system.

My new cooling system will employ the overflow tank as an expansion tank, I will mount it where the swirl tank is normally mounted, to give the engine compartment a "stock" look. I will not have a swirl tank in my system. There will be 2 air bleeds in the system, one on top of the radiator outlet tank, and one where coolant exits the motor. These bleeds will also be connected to the expansion tank, as Dave has described.

cowboy from hell

SO basically in theory we they are using the basic principles of a Hot Water heating system closed loop.

An air eliminator which they are doing it thru a tank ( why not thru a more modern method like a screen with a little float to let air out. and the second tank for expansion where we use bladder tanks the are under pressure on the other side of the bladder. My Mechanical backround is kicking in saying cant this be accomplished using some modern technology ... let see we use something called a SPIRO VENT for argument purposes 1/2 the size of the tank goes inline and has a float on top and relieves itself automaticly and also has a little drain on the bottom for getting rid of debris in the system which coleects on the screen .... then the expansion tank ...well convention heating system runs at 180 the expansion tank is sized on gallons of the system ... they may not make one small enough for a car but ... I will do some research ... I just think these two tanks are too large for the application ... but I'm betting the most cost effective ..... JUST BRAIN STORMING AGAIN.

Ron