Who has changed there radiators due to modifications?

[PeeBee]

Here is the engineering and the total myth busted. The thermal conductivity of copper is 1.9 times that of aluminium. So if you have the same area of core with the same number of fins and the same temps inside the radiator as outside for two radiators travelling under identical circumstances, the copper core will out perform the aluminium. The aluminium jobbie is a con. The thermal conductivity of copper is 223 BTU/hr.ft2F and the thermal conductivity for aluminum is 118BTU/hr.ft2F, So if you want to see a tangible difference in radiator performance, increase the only variable in the formula and that is AREA. assuming the temperature stays the same. Increasing only the volume inside the radiator will delay the temperature rise, not reduce the ultimate temperature. Additionally the other uncontrolled variable is the temperature, so you could only drive in cooler temps rather than hot temps to ensure you keep the radiator temps cool. There is a further variable due to air velocity, however that still comes down to the ability of to transfer the heat across the material boundary from inside to outside.

So really, all our efforts will be in vain to a large degree if we dont increase the surface area , decrease power/energy into the system by way of heat or find another way to more effectively shed heat by convection or radiation. If by chance you have installed an aluminium radiator and had a positive outcome, there must have been a change within one of the variables above as there is simply no magic going on. In our case we are typically boosting HP, ie energy into the system, but also driving quicker, whilst leaving the surface area the same or in some way increasing the thermal transfer due to higher density of cores and fins.

I run a copper core and always will. If I wanted to increase the efficiency I will get it modified to add more cooling fins per inch and if possible increase the cores by way of row depth. I would also induce more cooling air thru the core, in my case by running both a mech fan on the engine side of the radiator and a high volume elec fan on the other side of the radiator. I cannot physically change the outside boundary dimensions of the radiator without significant mods, so these are simply the limits. Just my thoughts, hope it helps.

Remember, this is a closed system, so energy in = energy out. If the out is less than the in, the energy is transferred and manifests as retained heat.

As to 2, 3, 4, 5 core radiators, they generally are more effective because of the greater depth of core thru the radiator, not the volume, so greater core area for heat transfer. As an example, every single Chev diesel conversion suffers from overheating to some degree, and the solution rolled out is to put in a larger multi core radiator, which more or less works until the owner pushes the vehicle harder as its not getting as hot, then the energy load goes up and he is basically at the same spot he started at. So the message is to get the energy load down, get the load down by virtue of weight, speed and driving style or go bigger on the radiator. I run a copper 4 core, and fully expect to be upgrading to a 5 core or even 6 once I start putting more energy into the closed system.

Waterless coolants work in a different way in that they raise the boiling point and reduce the occurrence of air bubbles. Air is an insulator, hence is the enemy of heat transfer efficiency. Air is also erosive when working in the steam state, so raising the boiling point helps; thats why the radiator cap is there as pressure helps with elevated temp management and why the correctly working radiator cap is important.