I always thought a catch can was a crude container, usually on a bit of wire to catch the drips from the radiator overflow line to stop making a mess of the racetrack. A recovery tank to me is a much more professional solution being properly plumbed in to the cooling circuit to retain any coolant expelled under expansion, to be fed back in to the system as it cools and contracts...
That is not all it takes for a recovery system to work. The radiator cap needs to be replaced with a cap that seals not only down in the neck of the rad but also around the outside of the neck as well. As the hot coolant cools it contracts, this creates a slight vacuum in the radiator. This vacuum pulls the coolant back into the rad. If the cap does not seal around the outside of the neck the recovery action will not take place.
That is not all it takes for a recovery system to work. The radiator cap needs to be replaced with a cap that seals not only down in the neck of the rad but also around the outside of the neck as well. As the hot coolant cools it contracts, this creates a slight vacuum in the radiator. This vacuum pulls the coolant back into the rad. If the cap does not seal around the outside of the neck the recovery action will not take place.
Yes, that is true provided the end of the hose in the recovery tank is located or secured to the bottom of the tank. That way is is submerged in coolant and it will be pulled back into the rad. I will be adding this system to my car soon, and am thinking of buying a second tank to use for windsheild washer fluid. This is the tank I will be using.
I have a plastic one I bought form AutoZone it is generic but fits very well in front of the windshields washer bottle and the radiator support. It was only like $6 with tax. And I think the type of radiator cap needed is referred as a vented type.
I just got one from Summit that has a little valve on the bottom if you care to release the fluid.
I ran an autocross event last year without anything.... a guy got mad at me cuz I laid down a little fluid. So I duct taped a water bottle on for the rest of the event...